Do Anti-Anxiety Medications Cause Weight Gain?

Classic anti-anxiety medications such as benzodiazepines show no association with weight gain. However, antidepressants, which are often prescribed as a first line treatment for anxiety, can lead to a high level of weight gain. 

First of all, I am not a doctor. I am just somebody who has taken different types of psychiatric medications, and struggled with weight gain from some of them. Anti-anxiety meds are a type of psychiatric, or psychotropic, medication. They regulate the brain chemicals that regulate emotions and thought patterns. There are five main types of psychiatric medications, of which anti-anxiety medications are one type. The other types are antipsychotics, stimulants, antidepressants, and mood stabilizers. Many psychiatric medications work by adjusting the number of major chemicals, also called neurotransmitters, in the brain. Psychotropic medications are not a cure for the underlying condition, and are often combined with therapy. 

Anti-anxiety drugs are also called “anxiolytics”, drugs that may be helpful to alleviate anxiety. It is ordinary for everyone to experience anxiety from time to time, but the type of anxiety that usually requires treatment is Generalized Anxiety Disorder, or GAD. It can cause excessive worry and distress, and make it difficult for a person to function.

There are a variety of different drugs that fall under the anti-anxiety umbrella. Probably the one that people think of as the most classic, are benzodiazepines. Common benzodiazepines are Valium, Xanax, and Klonopin. These drugs work to calm or sedate a person, by raising the level of inhibitory neurotransmitter GABA in the brain. 

Some other types of anti-anxiety medication are anticonvulsants (nonbenzodiazepine), antihistamines, and Azaperone (buspirone) and even antidepressants. Antidepressants are commonly used to treat anxiety in addition to depression, and other conditions. Antidepressants are actually often the first line of treatment to treat anxiety. Two classes of antidepressants used to treat anxiety are selective serotonin uptake inhibitors (SSRIs) and serotonin norepinephrine reuptake inhibitors (SNRIs). Some SSRIs for anxiety include Prozac, Celexa, Zoloft, Paxil, and Lexapro. Some SNRIs are Venlaxafine, and Cymbalta.

Psychiatric Drugs and Weight Gain

Weight gain is a common side effect of psychiatric drugs in general. Especially mood stabilizers and antipsychotics can lead to a lot of weight gain. This may be due to increased appetite and increased craving for high carb or sugary food, decreased physical activity due to lethargy, or changes to the underlying metabolism.  Some psychiatric drugs especially likely to cause weight gain are Olanzapine, Risperidone, and Seroquel. Antidepressants can also cause weight gain however, although not as commonly as antipsychotics and mood stabilizers.

Does Anti-Anxiety Medication Cause Weight Gain?

There has been relatively little research on the topic of whether anti-anxiety drugs cause weight gain. But there are no clear links between benzodiazepines, the most traditional anti-anxiety drug, and weight gain. However, antidepressants have been linked to weight gain, and they are often used as a first line treatment for anxiety. 

The antidepressants with the highest incidence of weight gain are “amitriptyline, citalopram, mirtazapine, nortriptyline, trimipramine, paroxetine, and phenelzine.” Weight gain is not guaranteed on any of these however. Some people gain weight on these drugs, but not all do. Weight gain is possible on Zoloft, Prozac, and Celexa, which we mentioned earlier are often used as first line treatments for anxiety. Some sources estimate that as many as 25% of people who take antidepressant drugs gain weight, and I have seen figures running even higher in some studies. 

It is not fully understood why antidepressants lead to weight gain. However, one theory is that both metabolism and hunger levels are affected. Antidepressants interfere with serotonin, a neurotransmitter that regulates mood and anxiety, and also controls appetite. Some of these changes may lead to craving carbohydrate rich foods, like pasta, desserts and bread.

What to do about Antidepressant caused Weight Gain?

Fortunately, there are some steps that you can take if you believe that your antidepressant prescribed for anxiety is causing you to gain weight. The first step that I would recommend, if your medication is causing you to gain a lot of weight, is talking to your doctor about taking a different medication. I have taken medications before, not anti-anxiety meds but other psychiatric medications, that have caused me to gain up to as much as 14 pounds within a couple of weeks. I decided that that was an intolerable side effect for me, and immediately requested to my doctor that I get off it and try something else. I would think that this would be obvious, but I have read forums where people claim to have gained over 100 pounds from their medication, and continue taking it despite all the risks associated with that level of weight gain.

I have also taken the drug Metformin, and that’s helped me a lot preventing medication induced weight gain. I’m not sure if it works for antidepressants though, so I would recommend doing some more research on that, or consulting your doctor. The other things that you can do about the weight gain are pretty standard. Especially if the drugs are causing milder amounts of weight gain. Try moving more, and eating less. Be sure to get at least 30 minutes of moderate intensity exercise a day. Work on portion control. You may want to think about eating more protein, to keep you full longer.

If you would like to check out a book that can help you to reduce your anxiety through mindfulness and meditation, you can find an e-book here on the subject.