Since its introduction in 1988, Prozac has become the most widely prescribed antidepressant in the world. An estimated 35 million people worldwide have taken the drug to combat depression, and its name has become as familiar a brand as Kleenex or Coca-Cola. Prozac belongs to a class of drugs called selective serotonin reuptake inhibitors (SSRIs), which increase the level of the neurotransmitter serotonin that is absorbed by receptors in the brain. Depression has been linked to an imbalance of neurotransmitters, chemicals that allow nerve cells in the brain to communicate. By regulating the flow of serotonin, drugs like Prozac, Paxil and Zoloft have been shown to alleviate many of the debilitating symptoms of depression and allow sufferers to function normally with few side effects. In early July, the Food and Drug Administration approved the use of Prozac to treat women with premenstrual syndrome (PMS). The drug will be marketed under a new name, Sarafem, to treat the mood swings and other symptoms women suffer from severe PMS.

While Prozac and similar antidepressants have been heralded as wonder drugs, concerns about their safety and effectiveness have arisen. Some Prozac users suffer from serious side effects such as sexual dysfunction, weight gain and facial tremors, but the drug's manufacturer, Eli Lilly, claims these problems are suffered by just a small percentage of Prozac users. But in his recent book, Prozac Backlash, Dr. Joseph Glenmullen, claims that up to 60 percent of Prozac users suffer from sexual dysfunction. The author has also called attention to a more controversial, less known possible side effect of Prozac: suicidal urges. Dr. Glenmullen claims that between 1 and 3 percent of his patients have become suicidal while taking Prozac, and that the drug's manufacturer Eli Lilly has suppressed studies that prove a link between suicide and Prozac use. The drug company denies these allegations, but in documents prepared for the patent application for a new form of Prozac, Eli Lilly claims that the new, improved formulation is less likely to produce suicidal thoughts. Critics say this improvement is tantamount to an admission that the original form of Prozac can cause this dangerous side effect.

While doctors and scientists continuing to churn out books and studies debating the merits and dangers of Prozac and other antidepressants, millions of depression sufferers remain grateful for the drug that allows them to shake off the debilitating burdens of the disease.

On One Hand...

Dr. Glenmullen points out in his book that Prozac is sometimes prescribed in cases when the patient is suffering from a temporary case of the blues, caused by such factors as a break-up or the loss of a job, rather than a serious case of clinical depression. In such cases, the patients may not be aware of the potentially dangerous side effects of the drug, which may not outweigh its benefits. Overuse of Prozac has also eclipsed the potential advantages of psychoanalysis, as people suffering from depression think they can be "cured" with a magic pill. In many cases, some form of talk therapy is necessary to uncover problems that may have triggered or exacerbated the patient's depression.

Given that Prozac is the most-prescribed antidepressant in the country, serious research needs to be devoted to the drug's possible dangerous side effects. If use of Prozac can lead to suicidal thoughts and acts, Eli Lilly needs to disclose this risk to users, not sweep these allegations under the rug.

On the Other Hand...

The shoddy science and sensationalism of Prozac Backlash and similar anti-Prozac books have exaggerated the risks of taking the drug. No comprehensive studies have shown that Prozac can cause suicidal urges, and anecdotal evidence does not prove the link. Prozac is not effective for all patients, and it is possible that individuals who do not experience relief from their symptoms may become despondent and feel suicidal. These cases cannot necessarily be blamed on Prozac.

For the majority of patients, the benefits of Prozac and other similar antidepressants far outweigh the side effects. With proper medical supervision, these drugs can help countless people reclaim their lives from the ravages of depression.

• An estimated 28 million people in this country, almost one in ten Americans, take antidepressants.

• Three out of ten depression sufferers don't respond at all to a given antidepressant, and the seven out of ten who respond do so only partially or find that the benefits wear out over time.

• Prozac sales, which total $3 billion annually, represent roughly a quarter of Eli Lilly's total revenue.

• Possible side effects of Prozac and other antidepressants can include appetite loss, rash, headache, anxiety, rapid pulse, coordination loss, trouble breathing, trouble urinating, dizziness, and drowsiness.

• Depression is on pace to be the world's second-most-disabling disease (after heart disease) by the year 2020.

Salon, U.S. News & World Report; NAMI