Does Prozac Make you Gain Weight or Weight loss – Comprehensive Analysis of Hunger, Appetite and Cravings from Fluoxetine

If you are taking an SSRI type of antidepressant, you may have noticed an increase in appetite, but does Prozac make you gain weight? This increased appetite phenomenon is known as the reverse serotonin effect or SRE loop. As a result of the increased appetite and food intake, most patients tend to gain weight while on these medications.

In this article, we will together go through the side effects of Prozac with a special focus on weight gain and weight loss. This will help you get an individual understanding of the symptoms that are you are likely to get that another person may not experience. Moreover, we will compare the antidepressants that cause the most weight changes.

An article published by The New York Times in November of 2018 brought attention to this side effect once again. The article focused on a growing body of evidence that suggests a correlation between taking Prozac and gaining weight. However, this was not the first time Prozac has been associated with weight gain. Let’s dive in!

Does Prozac Make you Gain Weight or Weight loss?

Contents

Does Prozac Make you Gain Weight or Weight loss?

Prozac (fluoxetine) may cause weight loss for some people, but can also cause weight gain in others. The weight changes with Prozac (fluoxetine) from our research was a weight loss that range from about 0.2% of body weight to a gain of about 1%. It is important to note that each person responds to antidepressants differently.

Weight loss associated with Prozac can be due to loss of appetite. Weight gain on the other hand can be associated with recovery from depression or anxiety disorders and carbohydrate cravings as you start to improve.

However, they are also observed to lose weight after some time since they start eating less. In addition, some people with depression develop cravings for specific foods such as carbs which can be resolved once the condition is managed. On the other hand, Prozac’s weight gain is a side effects that emanate from increased appetite and carbohydrate cravings.

It is important to note that the weight gain associated with Prozac may not be significant. Actually, the weight gain for patients taking fluoxetine for a long time does not vary from the weight gain experienced in people taking a placebo.

The common side effects of Prozac are nausea, sleepiness, and sexual problems, and weight gain. Antidepressants including Prozac, antipsychotic drugs, and mood stabilizers are common drugs that in most cases have a high potential to cause a weight gain.

Thus, even though Prozac may cause weight loss of about 0.2% of the body weight, losing weight by eating nutritious foods and getting regular physical activity is a better method. This is because the latter are sustainable methods of weight loss.

If you are gaining weight on Prozac, we recommend speaking to your doctor about the medication’s benefits and side effects.

How does Prozac make you gain weight?

It’s been observed that people who take antidepressants like Prozac have increased appetite and cravings for carbohydrates. Moreover, some people may have lost weight due to anxiety disorders or depression and thus start to regain weight when these conditions are managed. This is also known as a reverse serotonin effect or SRE loop which causes appetite changes.

The increased appetite results in weight gain, while the carbohydrate cravings lead to weight increase also at the same time. It is seen that after some time, most patients on these medications tend to start losing the weight gained due to reduced food intake.

Moreover, most of the adults tend to gain weight as they age whichever the medication they take. This may not be due to the increase in appetite and carbohydrate cravings, it is quite likely that these medications may lead to a person gaining weight because of reduced activity and metabolism.

However, this phenomenon can also lead to patients losing weight by eating less due to decreased desire for foods that are high in fat and sugar content.

Prozac and carbohydrate cravings

One of the most common side effects of Prozac is an increased appetite. This may be the result of serotonin being blocked in the brain, which leads to a craving for carbs and sugary foods. When someone eats sugary or starchy food, serotonin levels are increased in the brain.

High levels of serotonin lead to a feeling of well-being, happiness, and satisfaction. SSRI antidepressants such as Prozac work by blocking your ability to reabsorb serotonin in your brain. Therefore, when you eat carbs or sugared foods while taking Prozac, you end up feeling much better because your receptors are getting temporarily full of serotonin.

The benefits only last for a short time like 30 minutes so it’s important that this behavior is controlled and not done too often as it will lead to weight gain from excessive calorie intake.

The process does not stop at feeling better from carb cravings since patients also start having carb cravings after some time. This happens when eating less since most people who take Prozac typically have an increased appetite and eat more frequently than before they started taking the medication.

Does Prozac Make you Gain Weight or Weight loss? Hunger, Appetite and Cravings from Fluoxetine

Does Prozac cause food cravings?

Serotonin changes cause food cravings, especially carbohydrates. Prozac and other SSRIs increase the available serotonin in the brain by blocking its reabsorption.

The side effects of Prozac may include weight gain, due to the increased appetite. This is because in some people who take SSRI-type antidepressants develop cravings for carbohydrate-rich foods, such as bread, pasta, and desserts.

Therefore, some people develop a sweet tooth as a result of taking SSRIs such as Prozac. Therefore, you may find yourself eating more sugary things as well as carbohydrate-rich foods such as pasta.

Prozac and appetite increase

Increases in appetite occur with antidepressants and medication for anxiety disorders. Medications like Prozac are known to cause an increase in appetite. In addition, this is also observed with medications for anxiety disorders.

For example, you may experience an increase in appetite if you’re taking Zoloft for depression. If you’re taking Xanax for generalized anxiety, you may find that your appetite increases.

Prozac is a type of SSRI (selective serotonin reuptake inhibitor) and they are also linked with an increased appetite as well as carbohydrate cravings. This can lead to weight gain but how does Prozac make you gain weight?

Does Prozac affect your appetite?

Yes, with reduced anxiety and elevated serotonin, people get increased appetite. Prozac’s side effects include weight gain from increased appetite and carbohydrate cravings.

Prozac is a selective serotonin reuptake inhibitor (SSRI) type of antidepressant. SSRIs increase the effect of serotonin in the body.

The increase in serotonin levels due to SSRI medication reduces anxiety and elevates mood, which leads to increased appetite. In some cases, patients may crave food as well, as high levels of serotonin can lead to carbohydrate cravings.

This phenomenon is known as the reverse serotonin effect or SRE loop. As a result of the increased appetite and food intake, most patients tend to gain weight while on these medications. They are however also observed to lose weight after some time since they start eating less.

Prozac make me hungry

Antidepressants interfere with serotonin, the neurotransmitter that regulates anxiety and mood while also controlling appetite. Abnormal serotonin levels cause you to feel hungrier. When you take an SSRI antidepressant, it is supposed to increase serotonin levels in the brain.

Unfortunately, this also increases appetite and food intake. It’s been suggested that this is why people on antidepressants tend to gain weight. The good news is that many people stop gaining weight over time because they start eating less once the cravings for certain foods go away.

However, some people never lose weight and continue to put on pounds while taking antidepressants. If your antidepressant is making you gain weight, talk to your doctor about a different medication or reducing your dosage.

How does Prozac make you gain weight?

Weight gain from 20mg of Prozac

Yes, 20mg of Prozac can cause medium weight gain as compared to other SSRIs. 20mg of Prozac does cause weight gain as a side effect, but there is no conclusive evidence about the extent of the weight gained and how long it takes to notice the difference.

Some people have reported significant weight gain with 20 mg of Prozac, while others have not noticed any significant difference in their body weight.

Although Prozac can cause weight gain, it is not considered to be one of the most effective SSRI medications for managing depression or anxiety.

Did you gain weight on Prozac?

A small percentage of people eventually gain weight, especially when the medication is taken for six months or more (long-term). No matter what antidepressant you take, it’s possible to gain weight. And while some people will be more likely to gain weight than others, the exact cause of Prozac weight gain is not known.

So, what are the downsides of taking Prozac? Aside from the possibility of gaining weight, some people have negative side effects when they start taking an antidepressant.

These could include nausea, diarrhea, increased anxiety, headache, or dizziness. But in most cases, these side effects go away after a few weeks and if they don’t you might need to change medication.

Weight that you gain on Prozac

Things like your age, gender, genetics, medication dosage, and other medical conditions may have an impact on how much weight you gain.

The amount of weight that you gain is variable and can be from as low as 5 pounds to as high as 15 pounds. This is due to the various factors that contribute to weight gain.

Prozac has a number of side effects too, which can make matters worse for some people. It’s important to talk with your doctor about the various SSRI side effects before taking them.

If you are experiencing any of these symptoms or have already experienced them in the past, it’s best to talk to a doctor before taking Prozac and see whether there are alternatives available.

Antidepressants that cause the most weight gain

There are several antidepressants that are likely to cause weight gain. This is because weight gain is a possible side effect of most antidepressants. The ones that are associated with the most weight gain include:

  • Tricyclic antidepressants, including Amitriptyline (Brand name: Elavil), imipramine (Tofranil) and doxepin,
  • Tetracyclic antidepressants (TeCA) including mirtazapine (Remeron). It is also called an atypical antidepressant.
  • Monoamine oxidase inhibitors (MAOIs), including phenelzine (Nardil)
  • Selective serotonin reuptake inhibitor (SSRI) including paroxetine (Paxil, Brisdelle, Pexeva), sertraline (Zoloft), citalopram (Celexa) and escitalopram (Lexapro),
  • Serotonin-noradrenaline reuptake inhibitor (SNRI) including duloxetine (Cymbalta)

The above are antidepressants that are associated with weight gain.

Weight gain associated with antidepressants

The common side effects of antidepressants are weight gain, dry mouth, and eyes, insomnia or sleeping too much, sexual problems, and feeling agitated. The most common type of antidepressant is the SSRI (selective serotonin reuptake inhibitor) drugs like Lexapro, Paxil, Prozac, and Zoloft.

These medications can cause a weight gain of 10 pounds or more. To lead to this weight gain, there’s an increased appetite with these types of antidepressants that causes people to eat more than they normally would and crave carbohydrates.

Weight gain is so prevalent with SSRIs that it has been dubbed the “Prozac poop-out effect”.

Almost every antidepressant causes weight gain but in varying degrees and with differences in different individuals. Some people experience noticeable weight gain while others do not get any weight gain when using antidepressants.

What is the cause of weight gain when taking antidepressants?

Antidepressant-induced weight gain is tied to appetite changes. In a nutshell, when you’re taking an antidepressant, the medication causes increased appetite and carbohydrate cravings in some people with depression.

A person’s weight may fluctuate from week to week or month to month for many reasons. These include changes in exercise, fluid intake, and eating habits.

When it comes to antidepressants, these fluctuations may be magnified by the medication causing some patients to gain weight while others to lose weight.

Preventing weight gain while on Prozac

For those who are trying to lose or maintain their weight while on SSRIs, there is a way to do it. It will require work and discipline but it can be done. The first step is to participate in a formal weight management program such as Weight Watchers.

This will help you eat less and become more aware of your eating habits which can prevent overeating. Second, you’ll need to increase physical activity. Increase your time spent being active by about 30 minutes each day for one week and then add another 20 minutes every week until you have reached at least 120 minutes per day.

You should also try to spend less time sitting down, like when using your phone. Lastly, try not to eat too much of anything, even healthy foods like vegetables and fruit.

These methods may seem restrictive, but they’re worth the effort when it comes to managing the side effects of Prozac especially if you want to avoid gaining weight while taking the medication.

Does Prozac make it hard to lose weight?

Prozac does not typically lead to excessive weight gain but moderate weight gain with long-term use is possible. SSRIs have been shown to cause weight gain and cravings for sweets, carbs, and other high-calorie foods, which can add up quickly.

Studies have shown that this increase in appetite can last for as long as 14 days after discontinuation of the SSRI medication. Some people may experience weight gain while taking Prozac but this is not common.

For most patients, there is no significant change in weight with the short-term use of antidepressants. However, long-term use (14 days or more) of SSRIs has been associated with moderate weight gain averaging 7 pounds over 5 years. There are a few factors that could help you to maintain a healthy weight while on Prozac:

  1. Eat healthy — Monitor your diet and eat nutritious meals
  2. Exercise regularly — Consider incorporating exercise into your daily routine
  3. Drink plenty of water — Stay hydrated by drinking at least 8 glasses of water per day

Comparison of weight gain caused by Prozac or Zoloft

A 2008 study published in the Canadian Medical Association Journal found that while Prozac and Prozac-like drugs were associated with a general weight gain of about 5 pounds, Serotonin Reuptake Inhibitors (SSRIs) like Zoloft was linked to an average weight gain of about 12 pounds in a year.

People taking Prozac regularly for 2 years gained an average of 4.6 pounds, unlike Zoloft which led to an increase of more than 10 pounds on average.

It should be noted however that of all the SSRIs, fluoxetine (Prozac) and sertraline (Zoloft) caused the lowest weight gain. Worse off are TCAs which cause more weight gain as compared to SSRIs like Prozac and Zoloft.

Prozac: the basics

First, let’s start with the basics. Prozac is a brand name for fluoxetine, an antidepressant of the SSRI type. It is used to treat depression, obsessive-compulsive disorder (OCD), bulimia nervosa, and premenstrual dysphoric disorder (PMDD).

Prozac is also prescribed to treat anxiety disorders and panic disorders. These are just some of the many disorders that can be treated with the use of an SSRI antidepressant like Prozac.

The medication’s effectiveness in treating various psychiatric disorders has been demonstrated by three large studies involving patients who had not responded to psychotherapy or other drugs. There are many different side effects associated with taking Prozac like weight gain, headaches, and nausea.

Reverse serotonergic effect (SRE) and its consequences

SSRI antidepressants work by increasing brain levels of serotonin, a neurotransmitter. This chemical messenger is responsible for mood stabilization, sleep regulation, and sexual functioning. The medications in this class are fluoxetine (Prozac), citalopram (Celexa), fluvoxamine (Luvox), sertraline (Zoloft), and escitalopram oxalate (Lexapro).

The SRE loop works like this: SSRI antidepressants increase serotonin. Serotonin release suppresses your appetite and inhibits the production of ghrelin in the stomach. Ghrelin is a hormone that stimulates hunger, so it indirectly results in weight loss.

However, after some time, people start eating more to compensate for the increased appetite. As a result of this, they tend to gain weight while on these medications. It’s important to point out that not all patients will experience weight change due to their medication.

But because it’s such a common side effect most doctors will ask you about any changes you experience before prescribing an antidepressant-type medication.

One study found that 55-90% of patients who were prescribed Prozac gained significant weight after taking it for nine months or longer; however, it appears that the risk is much lower in women than in men.

Fluoxetine effects on metabolism

Prozac does not directly affect the way the body does its metabolism. However, due to an increase in serotonin levels and the associated side effects, metabolism may be affected.

Fluoxetine increases resting energy expenditure and basal body temperature in humans, which may be associated with weight loss. On the other side, it increases serotonin in the body which increases appetite and carbohydrate cravings leading to weight gain.

Weight loss is due to increased metabolism, also known as thermogenesis. Fluoxetine increases the rate at which your body burns calories by 5-6%. This means that while fluoxetine may cause you to gain some weight, it can also help you lose weight!

Do Prozac side effects go away?

Prozac causes mild side effects which in most cases go away within a few weeks after starting to take the medication regularly. This is because the body is able to adjust and tolerate the drug better. However, some side effects such as weight gain, sexual side effects, tremors, and suicidal thoughts and behaviors may persist for the duration of the use of the medication

If the side effects don’t go away, it is possible that the medication may need to be altered. Most antidepressants are not recommended if you have a history of eating disorders. Antidepressants can also cause weight gain, though most commonly in people who were already overweight before they started taking them.

A study by the University of Pennsylvania School of Medicine and Harvard Medical School found that people who are obese can experience as much as a 20-pound weight gain from antidepressants like Prozac, Paxil, Lexapro, and Zoloft.

The National Institutes for Mental Health says that for some people with depression, antidepressant medications can lead to an increase in appetite or cravings for specific foods. However, research suggests that long-term use of these medications does not lead to weight gain.

Conclusion

The serotonin levels in the brain are known to affect appetite and carbohydrate cravings. For example, if you have low serotonin levels, you may experience a decreased appetite and increased carbohydrate cravings.

If your serotonin levels are high, then you may be more likely to experience an increased appetite and decreased carbohydrate cravings. As a result of the increased appetite and food intake, most patients tend to gain weight while on these medications.

They are however also observed to lose weight after some time since they start eating less. In addition, some people with depression develop cravings for specific foods.

Prozac’s side effects include weight gain from increased appetite and carbohydrate cravings – but does Prozac also make you gain weight? The answer is no! It’s just one of the possible side effects of this medication.

The truth about Prozac is that it can increase your appetite, which may lead to weight gain. But not all antidepressants cause weight gain. It’s important to speak to your doctor about the possibility of weight gain as a side effect when taking this medication.

Eating more than usual is one of the most common Prozac side effects, sometimes leading people to put on pounds without realizing it (that’s where the term “Prozac pudge” comes from).

FAQs

Does Prozac make you gain weight?

Prozac’s side effects include weight gain from increased appetite and carbohydrate cravings. Too much uptake of carbohydrates can increase your weight. In the long term, SSRIs can cause a weight gain of 10 pounds or more. That depends on the person. Some people do gain weight while on SSRIs, like Prozac, and some people lose weight. Scientists are still studying why this happens in some patients but not in others.

What are the potential causes of increased appetite while on antidepressants?

One possible cause is the SRE loop or the ‘reverse serotonin effect’. This phenomenon is observed in many patients taking SSRI antidepressants and it involves an increase in appetite and food intake. Another possible cause of increased appetite is a change in taste perception, which can include decreased sensitivity to sweetness and saltiness, as well as an alteration of the body’s ability to perceive fat content in food (known as reduced saccharin preference).

I’m taking an SSRI antidepressant and am wondering if I should take it with a meal or after a meal?

Studies have shown that taking an SSRI with food helps inhibit the appetite for carbohydrate foods. For this reason, it is recommended to take your medication on an empty stomach and wait at least two hours before eating to avoid interfering with the metabolism of your food.

Do antidepressants make you crave sugar?

As mentioned earlier, people who are depressed often crave sugars and carbohydrates – these are called somatic cravings. They can be difficult to resist, but they shouldn’t be indulged in as they can lead to weight gain or obesity (read more about how antidepressants make you crave sugar). It’s important to note that these cravings might also be due to other factors such as eating disorders, sleep deprivation, hypoglycemia, or diabetes. You should consult your physician if these cravings persist as they could be symptoms of something more serious.

Sources:

https://pubmed.ncbi.nlm.nih.gov/10450256/#:~:text=Conclusions%3A%20Acute%20therapy%20with%20fluoxetine,related%20to%20recovery%20from%20depression.

https://www.verywellmind.com/prozac-and-weight-gain-1067021

Dr. David Barlow

David is a well-known researcher and author in the anxiety disorders area with extensive research on their etiology, nature, and treatment. He started the site to share his real-life experiences on the management of anxiety disorders with successful diagnosis and treatment being his motivation to write or review the content on this site.