Diet Pills & Antidepressants

If you are depressed and also have problems losing weight, antidepressants such as Prozac and prescription diet drugs such as phentermine may help improve your conditions, according to PubMed Health. Even though you can combine the use of antidepressants and diet drugs in most cases, you should speak with your doctor before adding weight loss drugs to your treatment plan, especially if you have a history of eating disorders or substance abuse.

Types of Diet Drugs

The Food and Drug Administration has approved three prescription appetite suppressants and one fat-blocker for use as weight loss drugs. The appetite suppressants phentermine, diethylpropion and phendimetrazine and the fat-blocking drug orlistat do not interact with antidepressants such as Prozac and nortriptyline or Pamelor, according to the University of Maryland Medical Center Drug Checker.

Using Appetite Suppressants

You can only use prescription appetite suppressants for up to 12 weeks at a time because the drugs may be habit-forming, warns the National Institute of Diabetes and Digestive and Kidney Diseases. If you ever abused drugs or alcohol, do not use prescription appetite suppressants such as phentermine. In rare cases, these drugs may worsen your depression or cause hallucinations, delusions and agitation.

Orlistat and Antidepressants

Orlistat stops your body from digesting the fat from the food you eat and passes it out through your bowel movements, according to the Mayo Clinic. You should take your antidepressants and other medications two hours before or after taking orlistat to prevent any problems with absorbing the medication. To reduce your risk of side effects such as uncontrollable bowel movements, oily gas or rectal pain, do not eat high-fat meals while taking orlistat.

Antidepressants and Weight Loss

Some antidepressants such as bupropion are prescribed “off-label” to help people lose weight, notes the National Institute of Diabetes and Digestive and Kidney Diseases. This practice is not controlled by the FDA. Also, other antidepressants, including Prozac, can cause weight loss and decreased appetite as side effects.

Other Diet Aids

Some doctors prescribe seizure treatments, sometimes also used to treat bipolar disorder, as weight loss medications, according to the National Institute of Diabetes and Digestive and Kidney Diseases. The usual candidates for this treatment regimen are the drugs topiramate, zonisamide and metformin. While these medications should not interact with antidepressants such as fluoxetine, bupropion or nortriptyline, they may cause side effects such as skin numbness, weakness or a metallic taste in the mouth.