Almost all medications have a wide variety of possible side effects, and this is true of the SSRIs, SNRIs and Wellbutrin. As with other drugs, only a few of these side effects are common. However, there is tremendous variation in response to medication. Do not hesitate to report any possible side effects to your psychiatrist and/or doctor, even if they are not typical of the drug you have been given. Some studies have indicated an increased risk of suicide in the first 3 to 8 weeks of taking these drugs among people under 25. Feelings of agitation and restlessness may be related to such risk. If you are starting SSRIs , you should be followed closely by your doctor and report any agitation or increased suicidal thoughts

The following is intended to be a general overview of the more common side effects of SSRIs, SNRIs and Wellbutrin. It is not a complete listing of all potential side effects:

Sexual side effects

A common side effect of Prozac, Zoloft, Paxil, Celexa, Effexor, Lexapro and Luvox is sexual dysfunction. People are highly variable in how they respond to these sexual side effects. The most common sexual side effect is delayed orgasm. The next most common is decreased libido—that is, sexual desire. A small proportion of men develop problems getting an erection. Delayed orgasm can range anywhere in severity from just noticeable to complete inability to achieve orgasm. Its impact on sex varies. It may prolong sex in a pleasurable way, or it may significantly inhibit pleasure. The orgasm itself may feel different.

Consequently, some people find the sexual side effects of these drugs tolerable while others find them extremely disturbing and discontinue medication or switch to another drug. These side effects reverse when the medication is stopped.

Sexual side effects occur in both women and men, although most of the clinical studies have been done on men. There is disagreement on what percentage of patients develop these side effects; possibly up to 75% of patients who take these drugs develop some sexual side effects. In some people the side effects disappear after a few weeks on the drug. Although inadequate data are available, Wellbutrin, Serzone, Effexor, and Remeron appear to have fewer sexual side effects, and Wellbutrin in combination with other drugs may even decrease sexual side effects.

Sexual desire may be diminished, or absent. Sometimes spontaneous thoughts of sex lessen or disappear. Erectile problems when they do occur generally respond well to treatment with Viagra, Levitra, or Cialis.

Assessing the sexual side effects of these drugs in women is somewhat difficult. Because of cultural prejudices, discussions (especially with male doctors) about sexual side effects are often omitted, insufficiently detailed or followed up in subsequent visits, or considered unimportant.

Sometimes people don’t care about sexual function when depressed. Since loss of sexual desire is a symptom of depression, some people who start these medications report an improvement in their sex lives despite delayed orgasm. Remember, however, that as your depression lessens, sex may become more important and sexual side effects more bothersome. At this point, you should feel free to raise this issue with your doctor.

Insomnia and agitation
Prozac, SNRIs and especially Wellbutrin frequently cause insomnia and a sense of restlessness, agitation, or nervousness that may range from mild to severe. Zoloft, Paxil, Celexa, Luvox, and Lexapro can also cause this. Again, occurrence of this side effect varies from person to person. It usually gets better after a few weeks and some psychiatrists prescribe sleep or anti-anxiety medication to use until these symptoms remit. With some people, the agitation may be severe enough to lead to discontinuation of the drugs. If you are starting medication and experiencing significant agitation or suicidal thoughts you should contact your health care provider.

All of these medications occasionally cause sleepiness in some people. With Remeron and Serzone this is a frequent problem. However, since both of these drugs can be taken once a day before bedtime, some people find this effect helpful.

Weight gain and loss
Only Remeron has been proven to lead to weight gain, however, there is a lack of adequate long-term studies of this issue. Prozac, Zoloft, Paxil, Luvox, and Wellbutrin can cause temporary loss of appetite and consequent weight loss when they are started. Many patients and clinicians describe weight gain with many of the SSRIs.
Other side effects
  • Prozac, Zoloft, Paxil, Luvox, Celexa, Effexor and Wellbutrin all may cause temporary nausea, stomachache, diarrhea, or headache. Generally these symptoms are mild and disappear after a few days to weeks.
  • Remeron and Zoloft may increase cholesterol levels.
  • Effexor may cause constipation and dry mouth and it causes high blood pressure in about 5% of people who take the drug. This happens in the higher dose range and is usually minimal.
  • Wellbutrin can cause seizures. This has occurred in less than 1% of people who take the drug. If you have a previous history of seizure disorders you should not take Wellbutrin and you should not take more than 200 mg. at one time or 450 mg. per day. Wellbutrin should not be used by people with eating disorders and alcohol abuse and dependence because of increased seizure risk.
  • Celexa, a relatively new drug, may cause the fewest side effects, including sexual ones, although the drug has not been used long enough to be sure of this.

The following is intended to be a general overview of the more common side effects of cyclic antidepressants. It is not a complete listing of all potential side effects:

These cyclic antidepressant medications vary primarily by side effects. Some are more sedative than others-that is, they make you feel sleepy or fall asleep. This can be useful if you are suffering from insomnia or troubling if it interferes with your daily activities.
Anticholinergic side effects
These drugs have what are referred to as anticholinergic side effects, some drugs more than others. These side effects include dry mouth, constipation, blurred near vision, and difficulty in urinating. Dry mouth is the most frequent symptom. Sucking on hard candies, especially citrus-flavored ones (preferably sugar-free ones for the sake of your teeth) can alleviate it.
Orthostatic Hypotension
Sometimes cyclic antidepressants cause a drop in blood pressure associated with change in posture that can lead to fainting or dizziness. This is referred to as orthostatic hypotension. Standing up slowly after being in a prone or squatting position can help prevent this.
Other side effects
  • Norpramin (desipramine) and Tofranil (imipramine) are two of the most widely prescribed cyclic antidepressants. Norpramin is one of the least sedating of the cyclic antidepressants and causes fewer anticholinergic side effects (dry mouth, etc.) than most other cyclic medications. It can be monitored in the blood with blood tests to determine if a therapeutic level is being reached. Norpramin causes fewer anticholinergic symptoms than Tofranil but some psychiatrists believe that it is less effective than Tofranil.
  • Elavil (amitriptyline) is a very sedating and causes severe anticholinergic side effects (such as dry mouth).
  • Vivactil (protriptyline) has the advantage of possibly being energizing and not causing weight gain. However, it has severe anticholinergic side effects and can cause anxiety and insomnia.
  • Ludiomil (maprotiline), Sinequan or Zonalon (doxepin), Surmontil (trimipramine), and Asendin (amoxapine) are antidepressants that are currently not widely used. They have no major advantages and they have problems that make them generally less desirable than other drugs. Ludiomil can increase the possibility of developing seizures. Sinequan is believed by many psychiatrists to be less effective than other cyclic antidepressants but is often used as an effective and non-addicting sleeping pill. Asendin can cause a serious and sometimes irreversible side effect known as tardive dyskinesia, an involuntary movement of muscles.
  • All of the cyclic antidepressants except Vivactil may cause weight gain.
  • People with narrow angle glaucoma or certain heart rhythm irregularities may not be able to take certain cyclic antidepressants.
  • In people under 25, antidepressants may increase the risk of suicidal thoughts.

Monoamine oxidase inhibitors (MAOIs) have significant side effects. They provoke dangerously high blood pressure when combined with a substance known as tyramine, which is contained in some food, beverages, and drugs. If you take MAOIs, you must avoid liver, cheese pizza, Chianti wine, certain beers and cheeses, herring, bologna and some other sausages, and a number of other foods as well as many cough and cold medications. Any meat you eat must be fresh. Coffee and chocolate should be consumed only in small amounts. If you take MAOIs you must get a dietary restriction list from your doctor. If you eat a “forbidden” food with no problem, you may still develop a severe reaction if you eat that food again.

Psychostimulants may lead to increased agitation or depression. Cylert occasionally causes serious liver damage and may be particularly risky for people taking multiple drugs for HIV infection.

Other side effects are jitters, insomnia, and loss of appetite and these medications can be addictive. When used for recreational purposes, these drugs have a high potential for abuse and addiction, which is why they are not widely prescribed. This problem may be outweighed by their utility in seriously ill patients (those with major symptomatic medical problems). An overdose may lead to paranoid episodes with loss of ability to judge reality.

Atypical antipsychotics can cause diabetes and increase cholesterol and triglyceride levels, which are also potential side effects of some HIV drugs. Other side effects include tardive dyskinesia—which is the involuntary movement of the body, often including the tongue and face. They can also rarely cause a fatal side effect known as neuroleptic malignant syndrome.

Last Reviewed: June 10, 2010