Selective Serotonin Reuptake Inhibitior

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SSRIs include alaproclate, citalopram (Celexa, Cirpam, Cirpamil, Eloptam), escitalopram (Lexapro), etoperidone (Etonin), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), paroxetine (Paxil, Pexeva), sertaline (Zoloft), and zimelidine (Normud, Zel).

The first generation of antidepressants included monoamine oxidase inhibitors (MAOIs), introduced in the 1950s, and tricyclics (TCAs) and tetracyclics, introduced in the 1960s. SSRIs are known as second-generation antidepressants and were first introduced in the 1980s (Patterson, 2006; Wong, Bymaster, & Engleman, 1995).

Fluoxerine (Prozac)Opens in new window was one of the first SSRIs developed; it was developed at Lilly Laboratories in 1972. Although it was not the first SSRI created and released on the market, it had fewer side effects than earlier SSRIs; two early SSRIs were withdrawn from the market because of their side effects.

Eli Lilly implemented highly effective marketing, therefore fluoxetine is often perceived as the first SSRI. Prozac was approved by the U.S. Food and Drug Administration in 1987 (Wong et al., 1995). Other types of antidepressants includes serotonin and norepinephrine reuptake inhibitors (SNRIs), norepinephrine reuptake inhibitors (NRIs), and atypical antidepressants.

Sometimes stimulants (e.g., Ritalin) are used to treat depression. One type of antidepressant may be used to augment treatment with an antidepressant of a different type.

The antidepressant effect of SSRIs is thought to be achieved by inhibiting the reuptake of the neurotransmitter serotonin, a chemical messenger in the brain. This inhibition allows more serotonin to be available for neurotransmission. While development of new antidepressant medications continues, the mechanism of action of many antidepressant medications is not clearly understood (Patterson, 2006).

Common side effects of SSRIs include anxiety, sedation, insomnia, nausea, gastro-intestinal upset, sweating, headache, restlessness, and sexual dysfunction (Preston, O’Neal, & Talaga, 2008).

A disadvantage of many antidepressants is that side effects are often experienced before therapeutic effects. For example, someone taking an SSRI may have to endure uncomfortable side effects for six to eight weeks before seeing any therapeutic benefits (i.e., reduction of target symptoms). This can cause some people to discontinue antidepressant treatment before realizing any benefits.

Serotonin syndrome can be caused by combining antidepressants with each other or with some opioids, antimigraine medications, stimulants (e.g.., amphetamines, cocaine), empathogenes (e.g., MDMA or Ecstasy), some herbs (e.g., St John’s wort), and various other medications and over-the-counter products.

Symptoms of serotonin syndrome may include rapid heart rate, sweating, shivering, dilated pupils, tremor or twitching, muscular rigidity, elevated temperature, confusion, agitation, delirium, hallucinations, coma, or death. Combining antidepressants and alcohol is not advisable; alcohol, a depressant, can worsen clinical depression and increase the toxicity of some SSRIs.

Sudden discontinuation of some SSRIs can result in a withdrawal syndrome. Withdrawal symptoms may include dizziness, nausea, sweating, insomnia, tremor, or confusion. A schedule for tapering off antidepressants should be discussed with a doctor.

Taking SSRIs during pregnancy may increase the risk of prenatal complications and could have adverse effects on newborns (Preston et al., 2008); potential risks should be discussed with a doctor. To avoid potentially harmful side effect and drug interactions, health care consumers should be sure that their doctors and pharmacists are aware of allmedications they are taking, including over-the-counter medications, herbs and natural remedies, and dietary supplements.