Does Anxiety Medication Make You Lose Weight?

Anxiety disorders involve excessive fear or worry that is hard to control and interferes with daily life. They include generalized anxiety disorder, panic disorder, social anxiety disorder, specific phobias, agoraphobia, separation anxiety disorder and selective mutism.

Anxiety disorder treatment

Anxiety disorders are often treated with psychotherapy, such as cognitive behavioral therapy. Many people also benefit from medication prescribed by a doctor or psychiatrist. These medications include:

Blood pressure drugs used off-label, such as clonidine (Catapres), propranolol (Inderal, Betachron E-R, InnoPran XL), nadolol (Corgard), and atenolol (Tenormin).
Selective serotonin reuptake inhibitors (SSRIs) such as paroxetine (Paxil), escitalopram (Lexapro), sertraline (Zoloft), fluoxetine (Prozac), fluvoxamine (Luvox), and citalopram (Celexa).
Serotonin and norepinephrine reuptake inhibitors (SNRIs) such as venlafaxine (Effexor and Effexor XR) and duloxetine (Cymbalta)
Tricyclic antidepressants such as imipramine (Tofranil) and clomipramine (Anafranil)
Benzodiazepines, usually for short-term use, such as lorazepam (Ativan), clonazepam (Klonopin), and alprazolam (Xanax).
Anti-anxiety drugs such as buspirone (BuSpar).

SSRIs and SNRIs are usually the first-choice medications for anxiety disorders. Other drugs are used in specific cases.

Anxiety itself can change your weight. Some people lose their appetite, while others eat more, including binge eating.

Anxiety medications can also cause weight gain or weight loss, depending on the drug and the person. Let's look at antidepressants, the drugs most often prescribed for anxiety.

What is the effect of antidepressants on weight?

A healthy number of antidepressants are linked to modest weight gain, especially with long-term use. Experts don't fully understand why.

One theory is that some drugs act on histamine and serotonin receptors that help regulate appetite. Feeling better can also bring back an appetite that depression or anxiety had suppressed.

A large 2024 study of more than 183,000 people, summarized by Harvard Health, found the average differences between common antidepressants were small, and many people gained no weight at all.

Antidepressants that cause weight loss

The list of antidepressant drugs is long. In that study, bupropion (Wellbutrin) was the only one linked to weight loss, about a quarter of a pound on average at 6 months. By 24 months, the trend had reversed to an average gain of about 1.2 pounds.

So bupropion is better described as weight-neutral than as a weight-loss drug. Loss of appetite is a listed side effect.

Bupropion is also one of the two ingredients in Contrave (naltrexone-bupropion), an FDA-approved prescription medicine for chronic weight management.

Wellbutrin side effects

Bupropion is used to treat depression and seasonal affective disorder, and, under the brand name Zyban, to help people quit smoking. It is not a standard treatment for anxiety, and it can cause anxiety and agitation as side effects. Common side effects include:

Loss of appetite
Constipation
Dizziness
Drowsiness
Dry mouth
Flushing
Hair loss
Headache
Increased sweating
Insomnia
Joint aches
Nausea
Nervousness
Restlessness
Tremors
Vomiting
Weakness
Weight loss
Abdominal pain

Additionally, some side effects may manifest in serious and life-threatening ways. To avert such a possibility, you should visit your health provider or see a doctor immediately you see some of the following effects;

Development of Allergic reactions, including skin rash, itching, difficulty breathing, etc.
Aggressiveness
Agitation
Changes in the menstrual cycle
Changes in sexual desire or function
Changes in vision
Chest pain
Confusion
Dark urine
Delusions or hallucinations
Difficulty breathing
Fainting
Fever, chills, or a sore throat
Hostility
Impulsiveness
Inability to sit still
Pale-colored stools
Panic attacks
Rapid or irregular heartbeat
Seizures
Severe headache
Swollen, blistered, or peeling skin
Unusual swelling
Worsening depression and suicidal thoughts
Yellow skin or eyes

The list of side effects is long. Some are mild and fade as your body adjusts. If side effects persist or get worse, contact your doctor right away.

The most serious risks are seizures and suicidal thoughts. Bupropion carries a higher seizure risk than most antidepressants, and the risk rises with dose.

According to MedlinePlus, your doctor will probably tell you not to take bupropion if you have had seizures. Never take more than one bupropion product at a time (for example, Wellbutrin and Zyban both contain bupropion).

People with eating disorders such as bulimia or anorexia also usually should not take it, because their seizure risk is higher.

If you are pregnant or planning a pregnancy, talk to your doctor about the risks and benefits before taking bupropion.

Does Lexapro cause weight changes?

Lexapro (escitalopram) is a selective serotonin reuptake inhibitor (SSRI). It is used to treat depression and generalized anxiety disorder. SSRIs increase the amount of serotonin available in the brain, which helps regulate mood.

In the study above, people on escitalopram gained about 1.4 pounds on average at 6 months and about 3.6 pounds at 24 months. Part of this may be appetite returning as anxiety or depression eases.

Effects vary from person to person, and some people's weight does not change.

So, what is the best antidepressant for weight loss?

No antidepressant should be taken to lose weight. Among common antidepressants, bupropion is the most weight-neutral, while many others are linked to modest gain. If weight is a concern, tell your doctor; it can help guide the choice of medication.

In Summary

Anxiety disorders are commonly treated with psychotherapy, medication or both.

The medications are often antidepressants. Bupropion (Wellbutrin) is the most weight-neutral, but it is not a first-line anxiety drug and has its own risks. Others, including Lexapro, are linked to modest weight gain on average.

These drugs affect people differently. First, do not self-medicate; second, talk to your doctor if a side effect persists.