Table of Contents
Introduction
Obesity is a serious health condition that affects millions of people around the world. It is linked to many other problems, such as heart disease, high blood pressure, type 2 diabetes, and even some cancers. Because of these risks, losing weight is not just about appearance—it can be a major step toward better health. For many people, changing their diet and exercise routine helps. But for others, lifestyle changes are not enough. This is when doctors may suggest weight-loss medications to support the process.
There are several medications that help with weight loss, and two of them are diethylpropion and semaglutide. These drugs work in very different ways and are used in different situations. Diethylpropion is one of the older weight-loss medications. It has been approved for many years and is known as an appetite suppressant. It works by changing chemicals in the brain that control hunger. Semaglutide, on the other hand, is much newer. It was originally used to treat type 2 diabetes. Later, doctors discovered that it also helped people lose a significant amount of weight. Because of this, a special version of semaglutide was approved for people who are overweight or have obesity, even if they don’t have diabetes.
Understanding how these medications compare is important for both doctors and patients. Many people are searching online to find answers about which drug works better, how much each one costs, what side effects they might cause, and how long they take to work. People also want to know who can take them and how safe they are for long-term use. These are all important questions, especially for someone trying to decide between the two.
One major difference between diethylpropion and semaglutide is how they are taken. Diethylpropion is a pill that is usually taken once or twice a day. It is only meant to be used for a short time—usually a few weeks to a few months. Semaglutide, however, is given as a shot once a week. It is designed to be used for a much longer period, often a year or more, and sometimes even for life if it keeps working well and is safe to continue.
Another difference is the type of medication each one is. Diethylpropion is a stimulant. This means it works in a way that is similar to amphetamines. Because of this, it may cause side effects like a fast heartbeat or trouble sleeping. It also has a small risk of addiction. This is why doctors usually only prescribe it for short periods. Semaglutide belongs to a newer class of drugs called GLP-1 receptor agonists. These drugs mimic a hormone in the body that helps control blood sugar, hunger, and how fast the stomach empties. This leads to feeling full sooner and eating less.
Cost is another area where the two drugs differ. Diethylpropion is available as a generic medication, which makes it much more affordable. Many people can buy it for a low price, and insurance often covers it. Semaglutide, on the other hand, is very expensive—especially the version used for weight loss. Some insurance plans do not cover it, making it difficult for many people to afford without help.
Choosing between diethylpropion and semaglutide is not easy. Each drug has its pros and cons. Some people may do well with a low-cost pill that helps reduce appetite quickly. Others may need a more powerful option that works in several ways, even if it comes with a higher price tag and is taken as a shot. Safety, long-term success, and how easy the medication is to use are all important things to think about.
This article compares these two medications by looking closely at how they work, how well they help people lose weight, how much they cost, what side effects they may cause, and what kind of people they are best for. The goal is to provide clear, easy-to-understand information to help guide smart decisions about weight-loss treatment.
What is Diethylpropion and What is Semaglutide?
Diethylpropion and semaglutide are two different prescription medicines used to help people lose weight. Both are approved by the U.S. Food and Drug Administration (FDA) for this purpose, but they belong to different drug families and work in very different ways. Understanding what each medication is and how it is used helps show how they compare for weight loss treatment.
Diethylpropion: What It Is and How It’s Used
Diethylpropion is one of the oldest weight loss medicines still in use today. It was first approved by the FDA in 1959. Diethylpropion belongs to a group of drugs called sympathomimetic amines. These drugs are similar in structure to amphetamines and act as stimulants. Because of this, diethylpropion changes how certain chemicals in the brain work.
The main way diethylpropion works is by reducing hunger. It affects brain chemicals like norepinephrine and dopamine, which play a role in appetite and alertness. When these chemical levels change, the brain sends fewer hunger signals. As a result, a person feels less hungry, eats less, and may begin to lose weight.
Diethylpropion is taken by mouth as a pill. It is available in two forms. The first is an immediate-release tablet that is taken two or three times each day before meals. The second is an extended-release tablet that is taken once a day, usually in the morning. The dose is chosen based on the patient’s weight loss goals and how well they tolerate the medicine.
This medication is only approved for short-term use. It is usually prescribed for a period of 8 to 12 weeks. The reason for this is that stimulant medications can become less effective over time. Also, there is a risk of side effects when used for long periods.
Because it is a stimulant, diethylpropion has a potential for abuse or misuse. For this reason, it is classified as a Schedule IV controlled substance in the United States. This means it has some risk for dependence, though lower than drugs in higher schedules. Doctors monitor patients carefully while they are using it. It is not recommended for people who have a history of substance use problems or certain heart conditions.
Semaglutide: What It Is and How It’s Used
Semaglutide is a newer type of weight loss medicine. It was first developed to treat type 2 diabetes and was approved by the FDA in 2017 under the brand name Ozempic. Later, in 2021, a higher dose of semaglutide was approved under the name Wegovy, specifically for weight loss.
Semaglutide is not a stimulant. It is part of a group of medicines called GLP-1 receptor agonists. GLP-1 stands for glucagon-like peptide-1. This is a natural hormone in the body that helps control blood sugar, digestion, and appetite. Semaglutide copies the action of this hormone.
The drug works by slowing down how fast food leaves the stomach. It also helps people feel full for a longer time after eating and reduces the desire to eat more food. In addition to these effects, semaglutide helps the body release insulin and control blood sugar levels, which can be especially helpful for people with type 2 diabetes.
Semaglutide is usually given as a weekly injection under the skin. Patients often use a pen device that contains the medicine and can give themselves the shot once a week. It is injected in the stomach, thigh, or upper arm. There is also a pill version of semaglutide, but for weight loss, the injected form is most commonly used and most effective.
Unlike diethylpropion, semaglutide is approved for long-term use. People may stay on the drug for several months or even years if they continue to lose weight and do not experience serious side effects. Because it does not have stimulant effects, it is not considered habit-forming and is not classified as a controlled substance.
Comparing Their Use and Purpose
Diethylpropion and semaglutide are both used to support weight loss, but their purposes and uses are different. Diethylpropion is best for short-term help in reducing appetite. It acts quickly, but it is not designed for long-term use. On the other hand, semaglutide is made for long-term weight loss and management. It works more gradually but can lead to greater total weight loss over time.
Diethylpropion is a tablet that must be taken daily, while semaglutide is most often given as a weekly injection. Diethylpropion affects brain chemicals in a way similar to other stimulants, while semaglutide mimics a natural hormone that regulates hunger and digestion.
The decision to use one of these drugs depends on many factors, including a person’s overall health, weight loss goals, how they respond to medications, and how long they plan to continue treatment. Each medication can help with weight loss, but in different ways and with different benefits and risks.
How Do Diethylpropion and Semaglutide Work Differently in the Body?
Diethylpropion and semaglutide are two medications used to help people lose weight. Even though they are both used for the same purpose, they work in completely different ways inside the body. Diethylpropion acts more like a stimulant, while semaglutide works more like a hormone. Understanding how each drug works can help explain why they cause different results, how long they should be used, and what side effects may happen.
How Diethylpropion Works
Diethylpropion is a type of drug known as a sympathomimetic amine, which means it works similarly to amphetamines. It was approved many years ago for weight loss and is still used today, usually for short-term treatment. Its main effect is to suppress appetite by changing how certain chemicals work in the brain.
The drug increases the levels of norepinephrine, dopamine, and serotonin in the brain. These are brain chemicals called neurotransmitters, and they help control feelings of hunger, energy, and mood. By increasing these chemicals, diethylpropion sends signals to the brain that reduce hunger. As a result, people taking diethylpropion tend to eat less and feel full sooner.
In addition to reducing appetite, diethylpropion also increases alertness and energy. This can make some people feel more active, which may lead to increased physical activity and greater calorie burning. However, the stimulant effect can also raise the heart rate and blood pressure. Some people may feel jittery, anxious, or have trouble sleeping. Because of these risks, diethylpropion is only approved for short-term use, usually for a few weeks to a few months.
Another important point is that diethylpropion is classified as a controlled substance, meaning it has a risk for dependence or abuse. This is another reason it is not usually used long term.
How Semaglutide Works
Semaglutide works very differently from diethylpropion. It is not a stimulant and does not act on the brain in the same way. Instead, semaglutide is a GLP-1 receptor agonist. This means it copies the action of a natural hormone in the body called glucagon-like peptide-1, or GLP-1 for short.
GLP-1 is a hormone made in the gut that helps control blood sugar and appetite after eating. When someone eats a meal, the gut releases GLP-1 to signal to the brain that the body is full. It also helps the pancreas release insulin to lower blood sugar. Semaglutide copies these effects and provides several weight loss benefits.
One way semaglutide helps with weight loss is by slowing down how quickly food leaves the stomach. When food stays in the stomach longer, people feel full for a longer time. This reduces the desire to eat again soon and leads to eating fewer calories.
Another way semaglutide works is by reducing appetite through the brain. It targets areas of the brain that control hunger and cravings, helping people feel satisfied with smaller portions of food. Because of this effect, many people on semaglutide find it easier to stick to a healthy eating plan.
Semaglutide also has benefits for people with type 2 diabetes. It helps the pancreas make insulin when blood sugar is high and slows the release of a hormone called glucagon that raises blood sugar. These effects help control glucose levels while also reducing body weight.
Semaglutide is usually given as a weekly injection under the skin. Unlike diethylpropion, semaglutide is approved for long-term use, and many people use it for several months or even years.
Main Differences in How They Work
The biggest difference between the two drugs is how they affect the body. Diethylpropion acts fast by increasing brain chemicals to reduce hunger, giving a quick but short-lasting effect. Semaglutide works more slowly by copying a natural hormone, helping the body feel full longer and reducing appetite in a more steady, lasting way.
Diethylpropion may help people lose weight quickly, but it often stops being effective over time and is not safe for long-term use due to its stimulant effects. Semaglutide tends to cause more gradual weight loss, but the results are often greater over time and last longer, especially if the treatment continues.
While diethylpropion is taken by mouth as a pill, semaglutide must be injected once a week. Diethylpropion is usually used for a few weeks, while semaglutide can be used for much longer periods with continued weight loss benefits.
Because of these differences, doctors may choose one medication over the other depending on a person’s medical history, weight loss goals, risk of side effects, and how long they need to stay on treatment.
Understanding how each medicine works helps explain why they are used differently and why they have different effects. Both can help with weight loss, but the way they do it—and how the body responds—is not the same.
How Effective Is Diethylpropion for Weight Loss Compared to Semaglutide?
Diethylpropion and semaglutide are both medications used to support weight loss. However, they differ in how much weight people typically lose when taking them. These differences are based on clinical studies and real-world data.
Weight Loss with Diethylpropion
Diethylpropion is an appetite suppressant. It helps people feel less hungry and eat fewer calories. It works quickly, and results can be seen within a few weeks of starting treatment. In short-term studies, people taking diethylpropion for 12 weeks lost an average of about 15.9 pounds. This is equal to around 7%–8% of their starting body weight.
In longer studies that followed people for up to one year, the average weight loss was about 10.6% of body weight. For someone who weighs 220 pounds, this would be around 23 pounds. These results were often better when people also made lifestyle changes such as eating a lower-calorie diet and increasing physical activity.
Diethylpropion is usually taken once or twice a day as a tablet. It is approved for short-term use, typically 12 weeks or less. This is because it is a stimulant that can affect the heart and may lead to dependence if used for too long. For these reasons, doctors usually do not prescribe it for long periods. As a result, long-term data on weight loss and maintenance with diethylpropion is limited.
Weight Loss with Semaglutide
Semaglutide works differently from diethylpropion. It is a GLP-1 receptor agonist. This means it acts like a hormone that helps the body feel full and slows down digestion. This leads to eating less food and losing weight over time.
In clinical trials such as the STEP studies, people taking semaglutide lost between 10% and 15% of their body weight over a period of about 68 weeks, which is a little over one year. The average weight loss was about 12.4% of starting weight. Some people even lost more than 20% of their body weight. For a person weighing 220 pounds, a 12.4% weight loss would equal about 27 pounds.
Semaglutide is taken once a week as a subcutaneous injection (under the skin). It is started at a low dose and slowly increased over time to reduce side effects. Unlike diethylpropion, semaglutide is approved for long-term use. It is meant to be used for chronic weight management, especially for people who are obese or overweight with other health problems such as high blood pressure, diabetes, or high cholesterol.
Comparison of Effectiveness
When comparing the two medications, semaglutide has shown greater weight loss in both clinical trials and real-world studies. While diethylpropion helps reduce weight in the short term, semaglutide provides more significant and longer-lasting results. The difference is especially noticeable over a period of one year or more.
Another key point is the pattern of weight loss. With diethylpropion, weight loss happens quickly, especially in the first few weeks. After that, the effects may level off. With semaglutide, weight loss begins more slowly but continues over many months. This ongoing weight loss can lead to greater total weight reduction over time.
Semaglutide also has an added benefit for people with type 2 diabetes. In those individuals, it helps with both blood sugar control and weight loss. Diethylpropion does not provide this added benefit.
However, the choice between the two may also depend on cost, availability, personal health history, and tolerance to side effects. Diethylpropion may be more affordable and easier to use for people who prefer pills and want short-term support. Semaglutide may be a better option for those needing long-term weight loss and who can manage injections and higher medication costs.
Both diethylpropion and semaglutide can support weight loss, but semaglutide has shown greater effectiveness and more sustained results in clinical research.
Which Drug Works Faster and What Is the Time Course of Effects?
Understanding how fast a weight loss drug works is important. Some people want to lose weight quickly for health or personal reasons, while others may prefer slow and steady progress. Diethylpropion and semaglutide are both used to help with weight loss, but they work at different speeds and follow different timelines.
Diethylpropion: Quick-Acting Appetite Suppressant
Diethylpropion is known for working fast. It belongs to a group of drugs called sympathomimetic amines, which act like stimulants. It helps reduce hunger by affecting chemicals in the brain that control appetite. Because of how it works, diethylpropion usually starts to reduce appetite within a few days. Many patients begin to notice weight loss within the first one to two weeks.
Clinical studies have shown that people using diethylpropion may lose about 1.3 pounds (0.6 kg) per week during the first 12 weeks. Over that time, total weight loss may range from 7% to 8% of body weight. For example, a person weighing 200 pounds might lose about 14 to 16 pounds in 3 months.
This fast action is one reason diethylpropion is often used for short-term treatment. Doctors usually prescribe it for up to 12 weeks at a time. Longer use is not recommended because the body can get used to the drug, and it may stop working as well. There is also a risk of side effects like high blood pressure or fast heartbeat if taken for too long.
Another reason diethylpropion is short-term is that it may cause dependence or be misused, similar to other stimulant-like drugs. That’s why it is often reserved for people who need to lose weight quickly, especially if they have not responded to diet and exercise alone.
Semaglutide: Slower Start, Longer Results
Semaglutide works in a different way. It is a GLP-1 receptor agonist. This means it copies a natural hormone in the body called GLP-1, which helps control hunger and blood sugar. Semaglutide helps people feel full longer, slows digestion, and reduces the urge to eat.
Unlike diethylpropion, semaglutide does not act right away. It must be started at a low dose and increased slowly. This slow start helps reduce side effects, especially nausea, which is common when the dose is too high too quickly. For example, the dose usually begins at 0.25 mg once per week and increases every four weeks until it reaches 2.4 mg per week, which is the full dose used for weight loss in people without diabetes (marketed under the brand Wegovy).
Because of this dose ramp-up, weight loss from semaglutide tends to start more gradually. People may begin to lose weight after three to four weeks, but larger changes are usually seen after two to three months. In clinical trials, most people experienced their biggest weight loss around 6 to 12 months after starting treatment.
One large study showed that people using semaglutide lost an average of 12.4% of their body weight over 68 weeks (about 1 year and 4 months). In some cases, people lost up to 15% or more. This shows that semaglutide may take longer to show full results, but the weight loss tends to be greater and more sustainable over time.
Comparing Time Course: Fast vs. Steady
The main difference between the two drugs is the speed of results. Diethylpropion usually leads to weight loss within a few weeks, while semaglutide builds results over several months.
Diethylpropion may be helpful for people who need a quick jump-start in weight loss. It might be used before surgery or when obesity causes immediate health risks. However, because it is not meant for long-term use, the weight loss might not continue after the drug is stopped.
Semaglutide, on the other hand, is designed for long-term use. It helps people lose more weight over time and maintain the weight loss, especially when combined with lifestyle changes like a healthy diet and physical activity. It also offers benefits beyond weight loss, such as improved blood sugar and possible heart protection in some patients.
Diethylpropion works quickly, often within the first week or two, and helps people lose weight in the short term. It is usually prescribed for up to three months. Semaglutide works more slowly, starting with small doses and gradually increasing. Most weight loss with semaglutide happens between three to twelve months, but the total amount lost is usually higher. These different timelines help doctors decide which medicine may be better for each person’s needs.
Side-Effect Profiles and Safety Considerations
Every medication can cause side effects. Some may be mild, while others can be more serious. Diethylpropion and semaglutide each have their own side-effect profiles. Knowing how these drugs affect the body helps patients and healthcare providers make safer choices.
Diethylpropion: Stimulant-Like Side Effects
Diethylpropion is a weight loss medication that works like a stimulant. It affects the brain by increasing the release of chemicals such as dopamine and norepinephrine. These chemicals help reduce hunger and boost energy. However, they can also lead to side effects that are common with stimulants.
One common side effect is an increased heart rate. Some people feel their heart beating faster or stronger than usual. Along with this, diethylpropion can raise blood pressure. This is why the drug may not be suitable for people who already have high blood pressure or heart disease.
Nervousness, restlessness, and trouble sleeping are also possible. Because diethylpropion stimulates the central nervous system, it can make it hard for some people to relax or fall asleep. Headaches and dry mouth are also frequently reported.
Another concern is the risk of dependency. Diethylpropion is chemically similar to amphetamines, which are known for their potential to cause addiction. The drug is classified as a Schedule IV controlled substance in the United States. This means it has a lower risk of abuse compared to Schedule II drugs like amphetamines but still carries some risk. For this reason, diethylpropion is typically only prescribed for short-term use—usually a few weeks at a time. Long-term use is discouraged to prevent dependency and to monitor for changes in heart health.
Semaglutide: Gastrointestinal and Hormonal Side Effects
Semaglutide is very different from diethylpropion in how it works and in the side effects it can cause. It is part of a group of drugs called GLP-1 receptor agonists. These drugs mimic a hormone in the body that helps control blood sugar and appetite.
The most common side effects of semaglutide are related to the stomach and digestive system. These include nausea, vomiting, constipation, diarrhea, and stomach pain. Most people experience these symptoms when they first start the medication. In many cases, the body adjusts over time and the symptoms lessen or go away. To help reduce these side effects, the dose is usually started low and increased slowly over several weeks.
Some people may also experience a reduced appetite. While this helps with weight loss, it can lead to decreased food intake and sometimes fatigue. Other reported side effects include burping, bloating, or feeling full quickly after eating.
There are also some rare but more serious safety concerns linked to semaglutide. One concern is a possible increased risk of thyroid C-cell tumors. This risk has been shown in animal studies, but it is not known if it affects humans the same way. Because of this, semaglutide should not be used by people with a personal or family history of a type of thyroid cancer called medullary thyroid carcinoma (MTC). It is also not recommended for people with a condition called Multiple Endocrine Neoplasia Syndrome Type 2 (MEN 2), which raises the risk for thyroid cancer.
Gallbladder problems have also been reported. Some people taking semaglutide may develop gallstones or inflammation of the gallbladder. Symptoms can include pain in the upper right part of the stomach, nausea, or fever.
In rare cases, semaglutide may lead to pancreatitis, which is inflammation of the pancreas. Signs of this condition include severe stomach pain, vomiting, and a high heart rate. Anyone who develops these symptoms should seek medical care immediately.
Drug Interactions and Combined Use
Both diethylpropion and semaglutide may interact with other medications. When taken together, they do not have a major direct interaction. However, caution is still needed. Semaglutide can lower blood sugar, especially in people who are also taking medications for diabetes. If diethylpropion is added, changes in appetite or food intake could affect blood sugar control further. Close monitoring by a healthcare provider is important in such cases.
Because diethylpropion stimulates the nervous system and semaglutide affects the digestive system and hormone levels, combining them may increase the chances of side effects. For example, one drug could make a person feel anxious or restless, while the other causes stomach upset. The combination may not be well tolerated by all individuals.
Diethylpropion tends to act quickly and works by stimulating brain activity. This brings with it the risk of elevated heart rate, high blood pressure, and potential dependence. It is best used for short periods and under close medical supervision.
Semaglutide, on the other hand, works through hormonal pathways and is taken over a longer period. It is often better tolerated over time but can cause gastrointestinal symptoms and has some serious warnings, especially related to the thyroid and pancreas.
Choosing between the two drugs involves weighing the benefits of weight loss against the possible risks of side effects. Medical history, tolerance, and long-term goals all play a role in finding the right medication. Regular follow-up and medical guidance are important for the safe use of either drug.
Who is a Suitable Candidate for Each Medication?
Choosing between diethylpropion and semaglutide for weight loss depends on the person’s health status, weight loss goals, and how long the treatment is expected to last. These two drugs work differently and are suited for different types of people. Some may do better with one than the other, depending on medical history and lifestyle.
Diethylpropion: A Good Option for Short-Term Weight Loss in Healthy Adults
Diethylpropion is an appetite suppressant that affects the brain to reduce hunger. It belongs to a group of medicines known as sympathomimetic amines, which are similar to amphetamines. It has been used for weight loss for many decades and is taken by mouth, usually once or twice a day.
This medicine is best suited for adults who are overweight or obese and need help with short-term weight loss. It may be used in people who are preparing for surgery or who need to lose a few pounds quickly to reduce certain health risks. Diethylpropion is approved for short-term use only, usually for a few weeks to a few months. It is not meant to be taken for long periods.
People who are otherwise healthy and do not have serious heart conditions, high blood pressure, or mental health disorders may be considered good candidates. Diethylpropion can increase heart rate and blood pressure, so it should not be used by individuals with cardiovascular disease, uncontrolled high blood pressure, or a history of stroke.
Since diethylpropion acts like a stimulant, it also has the potential to be habit-forming. For this reason, it is considered a controlled substance in many countries, including the United States. This means doctors must follow strict rules when prescribing it, and patients must use it carefully.
Diethylpropion is not recommended for people who have a history of substance abuse or eating disorders, as it could worsen these conditions. It is also not safe for women who are pregnant or breastfeeding. Children and teenagers are generally not prescribed this medication.
In general, diethylpropion may be considered for adults who need to lose weight quickly, are able to tolerate stimulant medications, and do not have health problems that would make the drug unsafe. These individuals must also be willing to follow a calorie-reduced diet and increase their physical activity while using the medication.
Semaglutide: More Appropriate for Long-Term Weight Management, Especially With Health Conditions
Semaglutide is a newer medication developed to help people with type 2 diabetes and obesity. It belongs to a class of drugs known as GLP-1 receptor agonists. This type of drug works by mimicking a natural hormone that helps control blood sugar levels, slows digestion, and reduces hunger. The result is lower appetite and gradual, steady weight loss over time.
Semaglutide is injected once a week. It is usually recommended for adults who have a body mass index (BMI) of 30 or more, or a BMI of 27 or more with weight-related medical problems. These problems may include high blood pressure, high cholesterol, type 2 diabetes, or sleep apnea.
This medication is better suited for people who need long-term weight loss support. Many people using semaglutide have already tried diet and exercise but were not able to lose enough weight on their own. Semaglutide is not a quick fix—it usually takes several months to show full results. However, the weight loss is often more lasting than with older medications.
Semaglutide is not a stimulant and is generally safer for people with heart conditions. However, it is not safe for everyone. People with a personal or family history of a rare type of thyroid cancer, called medullary thyroid carcinoma, or with a condition called multiple endocrine neoplasia syndrome type 2 (MEN 2), should not use semaglutide. It is also not recommended for use during pregnancy or while breastfeeding.
Some people experience side effects like nausea, vomiting, or diarrhea, especially when they first start the medication. These side effects are usually mild and often go away after a few weeks.
Semaglutide may be a better choice for adults who need to lose a significant amount of weight, especially if they also have other health conditions like diabetes or heart disease. It is helpful for people who want to lower their risk of long-term complications, such as heart attacks or stroke, as part of their weight loss treatment.
Key Differences Between Candidates for Diethylpropion and Semaglutide
Diethylpropion is a short-term option for people who are generally healthy and want to lose weight quickly. It is not suitable for long-term use and is not safe for those with certain heart conditions or a history of drug misuse. On the other hand, semaglutide is a long-term treatment for people who need ongoing help with weight loss, especially when other medical problems are present. It works more slowly but is linked to greater and more lasting weight loss in many cases.
Doctors consider a person’s health, weight, past medical problems, and personal goals when deciding which drug to prescribe. Both medications require lifestyle changes, such as eating fewer calories and being more active, to be effective. Proper follow-up with a healthcare provider is also needed to make sure the chosen treatment is safe and working well.
What Are the Costs and Insurance Coverage Differences?
When choosing between weight loss medications like diethylpropion and semaglutide, cost can be one of the most important factors. These two drugs differ not only in how they work, but also in how much they cost, how they are sold, and how likely they are to be covered by insurance. Understanding these differences can help patients and healthcare providers make informed choices.
Diethylpropion: Lower Cost and Generic Availability
Diethylpropion has been available for many decades. It is one of the older weight loss medications approved by the U.S. Food and Drug Administration (FDA). Because of its long history, it is now available as a generic drug. Generic drugs usually cost much less than newer brand-name medications.
A one-month supply of diethylpropion can cost between $20 and $50 without insurance, depending on the pharmacy. Some discount programs and online coupons can lower this cost even more. Since diethylpropion is available in tablet form and does not require special handling or refrigeration, it is easy to store and transport. This also keeps costs low for pharmacies and patients.
Many insurance plans cover diethylpropion, especially when prescribed for obesity or weight-related health problems like high blood pressure or type 2 diabetes. Since it is a generic medication, insurers are more likely to approve it without needing special authorization. In some cases, Medicaid and Medicare plans may also cover it.
However, diethylpropion is approved only for short-term use, usually up to 12 weeks. Because of this limit, people may not be able to use it as a long-term solution for weight management. If someone needs continued treatment, they may have to switch to another medication, which could lead to extra costs or insurance issues.
Semaglutide: High Cost and Coverage Challenges
Semaglutide is a much newer medication. It was first approved to treat type 2 diabetes under the brand name Ozempic, and later approved for chronic weight management under the brand name Wegovy. Unlike diethylpropion, semaglutide is a brand-name drug only. There is no generic version available at this time.
Without insurance, the list price for semaglutide can be around $1,300 to $1,400 per month in the United States. This adds up to over $13,000 per year. Even with insurance, coverage for semaglutide varies widely. Some private insurance companies do not cover weight loss medications at all. Others require special steps before approving coverage. These steps may include documentation of obesity, proof of other treatments that failed, and regular progress reports.
Government programs like Medicare often do not cover medications for weight loss. Medicaid coverage depends on the state. Some states may include semaglutide for patients who meet certain criteria, but others do not.
Pharmaceutical companies sometimes offer savings cards or discount programs for people with private insurance. These programs may lower the cost of semaglutide for a limited time. However, such discounts are usually not available for people using government insurance plans.
In addition to the cost of the drug itself, semaglutide is given as a weekly injection. This can add indirect costs, especially for patients who need help learning how to give the injections or need extra visits to a clinic. Some people may also need special storage tools, like refrigerated containers, when traveling.
Comparing Long-Term Value
While semaglutide is much more expensive than diethylpropion, some studies show that it may offer better long-term results. People who take semaglutide tend to lose more weight and are more likely to keep the weight off compared to those taking diethylpropion. If the weight loss leads to fewer health problems, there could be future savings on medical care. However, this potential benefit depends on the individual and whether they can continue the medication long enough to see those results.
Diethylpropion may be a better option for people looking for a short-term boost in weight loss at a lower cost. It is especially useful for patients who need to start losing weight before surgery or during a specific period when other treatments are not possible. Semaglutide, though more expensive, may offer a better option for people with obesity-related health conditions and a need for ongoing support.
Both cost and insurance coverage are important to consider when comparing diethylpropion and semaglutide. Understanding the full financial picture—including drug prices, insurance rules, and treatment duration—can help guide better decisions.
What are adherence rates and long-term persistence?
Staying on a weight loss medication over time is very important for success. This is known as adherence—how well a person follows the treatment plan, including taking the medicine as prescribed. Persistence means how long a person continues using the medicine without stopping. Both adherence and persistence help show how effective a drug can be in the real world, not just in clinical trials.
Semaglutide: High adherence and long-term use
Semaglutide has shown high adherence and persistence in many studies. One reason is that it provides steady, ongoing weight loss over time. Patients using semaglutide often see a gradual drop in body weight, especially after the first 12 to 16 weeks. This helps people stay motivated and committed to the treatment. In clinical trials like the STEP program, many participants stayed on semaglutide for over a year.
Semaglutide is usually given once a week as a subcutaneous injection. For some people, injections may seem harder to use than pills. However, because it only needs to be taken weekly, it fits easily into a routine. Many users find this dosing schedule convenient, especially compared to daily pills.
Real-world data also supports high persistence. A study published in 2024 looked at insurance claims and pharmacy records in the United States. It showed that people taking semaglutide for weight loss continued using it longer than those on older weight loss drugs, including stimulants like phentermine or diethylpropion. Some studies found that over 60% of semaglutide users were still taking the drug at 6 months, and around 45% at 12 months. These numbers are considered strong in weight loss treatment.
Side effects can sometimes affect adherence. Semaglutide is known to cause nausea, especially during the first few weeks. Doctors usually start patients on a low dose and slowly increase it to help the body adjust. This step-by-step dosing helps many people avoid or reduce side effects, making it easier to stay on the drug.
Another reason people continue semaglutide is that many experience improvements in health beyond weight loss. These include better blood sugar control, lower blood pressure, and reduced risk of heart disease. These benefits can encourage long-term use, especially for people with obesity and related conditions.
Diethylpropion: Short-term use and lower persistence
Diethylpropion has been available since the 1950s. It is an appetite suppressant that works by stimulating the central nervous system. It is taken by mouth, usually once or three times per day, depending on the type (immediate-release or extended-release).
While diethylpropion is effective for short-term weight loss, it is generally prescribed for no more than 12 weeks. This is partly because it is a controlled substance. The U.S. Drug Enforcement Administration (DEA) classifies it as a Schedule IV drug due to its potential for misuse or dependence. Doctors often avoid long-term prescriptions of stimulant drugs like diethylpropion.
Because of these restrictions, long-term persistence is naturally lower. Even if a person is doing well on the drug, many stop after 2 or 3 months, simply because guidelines recommend limiting use. Studies show that only a small number of patients continue using diethylpropion beyond 3 to 4 months.
Adherence may also be affected by side effects. These can include dry mouth, insomnia, increased heart rate, and higher blood pressure. These stimulant-like effects can be uncomfortable and lead some people to stop the medication early.
Unlike semaglutide, diethylpropion does not have many long-term studies showing benefits beyond weight loss. There is also limited data on its effects after one year. Because it is not meant for long-term use, it may not support continued weight loss or maintenance over time. Once the drug is stopped, people often regain some of the weight they lost.
Semaglutide tends to have higher long-term adherence and persistence compared to diethylpropion. Its once-weekly dosing, slow and steady weight loss, and added health benefits encourage many users to stay on the medication for 6 to 12 months or more.
Diethylpropion, in contrast, is usually used for a short time and has fewer long-term users. Its stimulant properties and side effects limit how long it can be safely taken. This makes it more suitable for short-term use or for people who need a temporary boost in appetite control.
Semaglutide shows better long-term use in both clinical studies and real-world practice. Diethylpropion may work well for a brief period, but it is not designed or approved for ongoing weight management.
Are There Head-to-Head Studies or Direct Comparisons Between Diethylpropion and Semaglutide?
There are currently no large, well-controlled clinical trials that directly compare diethylpropion and semaglutide for weight loss. This means researchers have not conducted a study where both drugs were tested side-by-side in the same group of people under the same conditions. Without this type of study, it is more difficult to make exact comparisons between how well the two medications work, how safe they are, and how patients respond to each over time.
Even though there are no direct comparisons, it is still possible to look at the results of separate clinical trials for each drug. These trials offer valuable information about how each medication helps with weight loss and how people tolerate them.
Clinical Trials on Diethylpropion
Diethylpropion has been used for weight loss since the 1950s. It is one of the older medications approved to help with weight loss in adults with obesity. Clinical trials show that diethylpropion can help reduce weight when used with a low-calorie diet and lifestyle changes. One study found that people lost an average of about 15.9 pounds (7.2 kg) after 12 weeks of using diethylpropion. Over a full year, some people were able to lose about 10% of their starting weight.
However, diethylpropion is only approved for short-term use—usually for a few weeks to a few months. It is not meant for long-term weight loss management. Because it works as a stimulant, it can affect the nervous system and may lead to increased blood pressure, faster heart rate, or trouble sleeping. It can also lead to dependence or abuse in some people. For these reasons, doctors usually limit its use and monitor patients closely.
Clinical Trials on Semaglutide
Semaglutide is a newer medication that was first used for diabetes treatment and later approved for weight loss. The most well-known trials for semaglutide include the STEP series (Semaglutide Treatment Effect in People with obesity). These were large, well-designed studies with thousands of participants.
In one trial, people taking semaglutide lost an average of 14.9% of their body weight over 68 weeks. Another study showed that people with obesity and type 2 diabetes lost around 9.6% of their weight over the same time period. These results were better than what researchers have seen with most older weight loss drugs, including diethylpropion.
Semaglutide is also approved for long-term use, which makes it more suitable for people who need ongoing weight loss support. However, the medication is given as a weekly injection, which can be a barrier for some patients. It also comes with possible side effects like nausea, vomiting, and stomach pain. In rare cases, it can cause more serious problems such as pancreatitis or gallbladder disease.
Indirect Comparisons
Since diethylpropion and semaglutide have not been tested in a head-to-head trial, doctors and researchers rely on indirect comparisons. This means they compare the results of different studies by looking at average weight loss, side effects, and how long people stay on the medication. While this method is not perfect, it can still help guide treatment decisions.
For example, comparing the trial results shows that semaglutide leads to greater weight loss, especially when used for over a year. It also appears to help more people keep the weight off over time. On the other hand, diethylpropion may lead to quicker short-term weight loss but does not maintain those results as well over the long term. Its stimulant properties also limit how long it can be safely used.
Safety profiles differ too. Diethylpropion may cause problems related to the heart and nervous system, while semaglutide is more likely to cause gastrointestinal symptoms. These differences matter when deciding which medication might be right for a person based on their health conditions, lifestyle, and weight loss goals.
Why No Head-to-Head Studies Exist
One reason for the lack of direct studies may be that these drugs come from very different eras. Diethylpropion is an older medication, while semaglutide is new and supported by more recent research funding. Also, pharmaceutical companies usually fund trials for their own drugs and may not have a reason to compare their product to an older generic medication like diethylpropion. As a result, doctors rely on available evidence and their clinical experience to choose the most appropriate treatment for each patient.
Even without head-to-head trials, available research shows clear differences between diethylpropion and semaglutide. Semaglutide provides more long-term weight loss and is safer for extended use, while diethylpropion works well for short-term results but comes with limits due to side effects and dependency risks. Ongoing research may provide more direct comparisons in the future, but for now, treatment decisions depend on individual health needs, preferences, and access to care.
Conclusion
Diethylpropion and semaglutide are two medications approved for helping people lose weight. Both work in different ways, have different safety profiles, and come with very different costs. They are also used in different types of patients and for different lengths of time. Understanding the differences between these two drugs is important for doctors and patients trying to find the most effective and safe treatment for weight loss.
Diethylpropion has been used since the 1950s. It is a type of stimulant. This means it works by affecting chemicals in the brain to reduce appetite. People who take diethylpropion often feel less hungry and may eat less. This can lead to weight loss over a short period. Most of the time, this drug is used for only a few weeks or months. It is not recommended for long-term use because it can cause side effects like high blood pressure, fast heart rate, and trouble sleeping. Diethylpropion may also lead to dependence if taken for too long. Because of this, it is classified as a controlled substance and must be prescribed with care.
Semaglutide is a newer drug. It belongs to a class of medications called GLP-1 receptor agonists. These drugs work in a different way. Instead of acting on the brain like a stimulant, semaglutide copies a natural hormone in the body. This hormone helps the body control blood sugar, delay stomach emptying, and send signals of fullness to the brain. People taking semaglutide often feel full faster and for longer. This helps them eat less and lose weight over time. Unlike diethylpropion, semaglutide is used for long-term weight management. In clinical studies, people who used semaglutide lost more weight compared to those who used diethylpropion or similar medications.
One key difference between the two drugs is how much weight people usually lose. Diethylpropion may help people lose about 7 to 10 percent of their body weight, often within 12 weeks. In contrast, semaglutide has been shown to help people lose around 11 to 15 percent of their body weight, but this takes several months. This means semaglutide works more slowly at first, but the weight loss is often greater and more sustained. The longer someone stays on semaglutide, the more weight they may lose, as long as they also make changes to their diet and activity levels.
Both drugs come with side effects. Diethylpropion can cause symptoms that are common with stimulants, such as nervousness, dry mouth, and increased blood pressure. There is also a small risk of abuse or addiction. Semaglutide, on the other hand, mostly causes stomach-related side effects like nausea, vomiting, or diarrhea. These side effects are usually temporary and may improve over time. However, semaglutide also has warnings for rare but serious risks, such as thyroid tumors and gallbladder problems.
Cost is another major difference between these medications. Diethylpropion is a generic drug and is usually much cheaper. It comes in tablet form and is taken once or twice a day. Many insurance plans cover diethylpropion, especially if it is prescribed for a short period. Semaglutide is expensive, especially under brand names like Wegovy and Ozempic. It is often not covered by insurance unless the patient also has type 2 diabetes or meets specific medical criteria. Semaglutide is given as a weekly injection, which may also be a barrier for some people.
Long-term use is also different. Diethylpropion is usually prescribed for a few weeks to a few months. After that, doctors often stop it due to safety concerns. Semaglutide is designed to be used for many months or even years. People who stay on semaglutide longer tend to lose more weight and keep it off better than those using short-term medications like diethylpropion. Studies also show that people are more likely to stick with semaglutide treatment over time, even though it requires injections.
Direct comparison studies between diethylpropion and semaglutide are limited. Most of the information available comes from separate studies on each drug. These studies suggest that semaglutide provides greater weight loss, longer-lasting results, and fewer safety concerns related to the heart or nervous system. However, it is also more expensive and less convenient for some people.
In summary, diethylpropion and semaglutide are both approved tools for weight loss, but they are very different. Diethylpropion works faster at the start and costs less, but it is only for short-term use and has more risks related to the heart and possible addiction. Semaglutide takes longer to show results, costs much more, and requires weekly injections, but it offers greater weight loss and can be used safely for the long term. Choosing between these two depends on a person’s health needs, medical history, budget, and ability to stay on treatment. A healthcare provider can help decide which option is better based on each person’s situation.
Research Citations
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Questions and Answers: Diethylproprion vs Semaglutide
Both drugs are used for weight management in individuals with obesity or overweight conditions, often alongside diet and exercise.
Diethylpropion is a sympathomimetic amine that works as an appetite suppressant by stimulating the central nervous system (similar to amphetamines).
Semaglutide is a GLP-1 receptor agonist that mimics the incretin hormone to reduce appetite, slow gastric emptying, and improve insulin sensitivity.
Diethylpropion is taken orally as tablets, usually 1-3 times daily. Semaglutide is typically administered as a once-weekly injection.
Semaglutide is better suited for long-term use, while Diethylpropion is generally prescribed for short-term use only (typically up to 12 weeks).
Diethylpropion may increase blood pressure and heart rate, posing cardiovascular risks. Semaglutide has a cardioprotective effect in some patients with type 2 diabetes.
Semaglutide is also FDA-approved for type 2 diabetes under brand names like Ozempic and Rybelsus. Diethylpropion is not approved for diabetes management.
Common side effects include dry mouth, insomnia, increased heart rate, and nervousness.
Common side effects include nausea, vomiting, constipation, and diarrhea. These often improve over time.
Semaglutide has shown greater average weight loss (up to 15% or more of body weight) in clinical trials compared to modest weight loss with Diethylpropion.
