About one in 10 Americans over the age of 12 takes antidepressants, an increase of nearly four-fold since the early 1990s. Despite the popularity of these drugs, some critics argue that they have a relatively small effect on mild depression when compared to a placebo. People with severe forms of depression seem to get greater benefit. Although the most commonly prescribed antidepressants vary from year to year, so far all these drugs have proven about as effective as each other and have similar side effects.
SSRIs are the most commonly prescribed antidepressants. Scientists don't yet understand how these drugs work, but they are thought to affect the balance of serotonin in the brain. Serotonin is a chemical signal that brain cells send to each other to communicate. SSRIs block the reabsorption of serotonin by these cells, which may boost the levels of this signal.
As well as potentially relieving depression, SARI antidepressants tend to make people feel sleepy. Scientists don't yet understand how these drugs work, but they are thought to affect the balance of serotonin in the brain. Serotonin is a chemical signal that brain cells send to each other to communicate. Like SSRIs, SARIs block the serotonin from being reabsorbed, but they also block the serotonin signal from being received by cells.
Scientists don't yet understand how SNRI antidepressants work, but they are thought to affect the balance of serotonin and norephinephrine in the brain. Serotonin and norepinephrine are chemical signals that brain cells send to each other to communicate. SNRIs block the reabsorption of serotonin and norepinephrine by these cells, which may boost the levels of these signals.
| Generic name: | Sertraline |
| Brand name: | Zoloft |
| Available as a generic? | Yes |
| Drug class: | SSRI definition |
| Side effects: | Higher rates of diarrhea compared to other SSRI antidepressants |
| Number of prescriptions: | 38,857,000 |
| Sales: | $118,910,000 |
| Generic name: | Citalopram |
| Brand name: | Celexa |
| Available as a generic? | Yes |
| Drug class: | SSRI definition |
| Side effects: | Higher rates of diarrhea compared to other SSRI antidepressants |
| Number of prescriptions: | 38,785,000 |
| Sales: | $58,375,000 |
| Generic name: | Fluoxetine |
| Brand name: | Prozac |
| Available as a generic? | Yes |
| Drug class: | SSRI definition |
| Side effects: | Higher rates of diarrhea compared to other SSRI antidepressants |
| Number of prescriptions: | 25,546,000 |
| Sales: | $116,692,000 |
| Generic name: | Trazodone |
| Brand name: | Desyrel (no longer available) and Oleptro |
| Available as a generic? | Yes |
| Drug class: | SARI definition |
| Side effects: | More likely to cause drowsiness than SSRI antidepressants (often prescribed as a sleep aid) |
| Number of prescriptions: | 24,455,000 |
| Sales: | $62,854,000 |
| Generic name: | Duloxetine |
| Brand name: | Cymbalta |
| Available as a generic? | No (until 2014) |
| Drug class: | SNRI definition |
| Side effects: | Patients more likely to discontinue treatment because of side effects compared to SSRI antidepressants |
| Number of prescriptions: | 18,891,000 |
| Sales: | $4,716,712,000 (still under patent protection)
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