Test Your Knowledge

Newer antidepressants are generally safer and better tolerated than older antidepressants. Most side effects are temporary and/or dose-related, which means that they improve when the dosage is reduced and worsen when the dosage is increased.

The U.S. Food and Drug Administration (FDA) issued a warning that antidepressants may increase the risk of suicide in certain people. The reason for this side effect is not fully understood. However, it may be because antidepressants often cause improvements in physical side effects of depression, such as fatigue, before providing relief of emotional side effects, such as a sad mood or anxiety. In some cases, this may give individuals who had previously contemplated suicide the energy to act on their impulse. Therefore, it is important for people taking antidepressants to be monitored for unusual behavior.

Side effects occur frequently during the early phases of antidepressant treatment. A physician can usually suggest tips on how to manage most of these, which may include:

• Nausea. May be lessened if the medication is taken with a meal.
  
  
• Weight gain. Eating healthy foods and exercising may help reduce this side effect, which appears to occur most commonly with the tricyclic antidepressants (TCAs).
  
  
• Fatigue. Taking the medication shortly before bedtime can help reduce this side effect.
  
  
• Insomnia. Taking the medication in the morning may help reduce this side effect, which appears to be more likely to occur with selective serotonin reuptake inhibitors (SSRIs).
  
  
• Dry mouth. Sipping water, sucking on ice chips and chewing gum may help reduce this side effect, which is most likely to occur with TCAs.
  
  
• Constipation. Eating plenty of fiber may help reduce this side effect, which is most likely to occur with TCAs.
  
  
• Dizziness. Taking the medication at bedtime can help reduce this side effect.
  
  
• Agitation or restlessness. Exercising may help reduce this side effect, which is most likely to occur with SSRIs.
  
  
• Sexual dysfunction. Includes a decreased libido and problems achieving orgasm. This is most likely to occur with the SSRIs. Switching to an antidepressant that is not associated with sexual dysfunction, such as bupropion, nefazodone or mirtazapine, or an serotonin and norepinephrine reuptake inhibitor (SNRI), may help reduce this side effect.

Patients may experience withdrawal if an antidepressant is discontinued abruptly. Symptoms of withdrawal usually go away after the drug is out of the patient’s system or the patient’s body has had a chance to adjust to the medication change. The symptoms of withdrawal include the common side effects of the medication as well as headache, irritability, diarrhea and tingling sensations.

Serotonin syndrome is a rare but serious risk of any medication that increases serotonin levels and must be identified as rapidly as possible. It occurs most commonly from drug interactions (e.g., using both monoamine oxidase inhibitors or TCAs and SSRIs). This condition may eventually progress to rhabdomyolysis (destruction of muscle) and potentially fatal liver failure. Initial symptoms may include confusion and flushing (becoming red in the face).

The norepinephrine and dopamine reuptake inhibitor (NDRI) bupropion causes little or no weight gain and minimal sexual side effects. In rare cases, it may cause jitteriness or akathisia (restless arms and legs). Common side effects include gastrointestinal upset and excessive sweating. Bupropion may also cause seizures.

In rare cases, serotonin and norepinephrine reuptake inhibitors (SNRIs) may cause increased blood pressure, rapid heart rate and confusion.

The serotonin modulator nefazodone may cause confusion or vision changes (e.g., blurred vision). Nefazodone should not be used by patients with liver problems. In 2002, the U.S. Food and Drug Administration (FDA) issued a warning regarding the risk of liver failure in patients treated with nefazodone.

The serotonin modulator trazodone causes significant drowsiness and is often given in low doses along with other antidepressants to treat insomnia although it is not approved by the FDA for the treatment of insomnia. Other side effects may include dizziness, lightheadedness when rising, dry mouth and blurred vision. It may also exacerbate cardiac problems. In addition, trazodone is the only antidepressant that may cause priapism (persistent, painful erections). Trazodone-induced priapism may not go away on its own and surgery is typically required in such cases.