Prozac® is a medication first introduced in the 1980s by the company Eli Lilly®. It is an antidepressant that belongs to the class of medications called selected serotonin reuptake inhibitors (SSRIs), which help to free up serotonin in the body and can regulate mood. SSRIs were designed as a replacement for other antidepressants called tricyclic antidepressants (TCAs) that worked in similar ways but had a heavy side effect profile. Many people hailed the advent of Prozac® and other SSRIs because they seemed as effective in the treatment of a variety of conditions, including major depression, and panic disorder without as many side effects. In particular, Prozac® (also available in generic form as fluoxetine) has been shown to be effective for some people in treating not only the above disorders but also obsessive-compulsive disorder, bulimia, and premenstrual dysmorphic disorder.
It’s important to understand that each person’s response to Prozac® will be different. For some people, it is a miracle drug that begins to alleviate symptoms of depression or other illness within a few weeks of starting treatment. Others may have no or very limited response to the medication. Usually people can expect some relief from symptoms within about three to six weeks of starting the drug, but doses may need to be increased for full effect, or sometimes it simply won’t work. In this case, another antidepressant may be more appropriate.
There are some extremely serious side effects associated with fluoxetine. Especially in children, teens and young adults it can cause or increase suicidality. This needs to be watched very carefully in people prescribed Prozac®. If an increase in suicidal behavior, thoughts or feelings occurs, this should be immediately reported to the prescribing physician. Other dangerous side effects that may occur include blistering of the skin, extreme headache, confusion, high fever, vomiting or diarrhea, muscle rigidity and rapid heart rate. These symptoms require immediate medical care.
Many people who take Prozac® won’t have dangerous reactions to it, but they can have side effects that usually occur when the medication is first taken, and then recede over time. Some early side effects include stomach upset, changes in weight (up or down), trouble sleeping, cold-like symptoms, and dry mouth. A few people have difficulties with fluoxetine because it may cause disinterest in sex, reduced libido, difficulty maintaining erections or difficulty achieving orgasm. Not everyone will have all of the side effects, and some will have few to none.
There are medications that can conflict with fluoxetine, and it’s best to check all medications with a doctor before accepting a prescription for this drug. Some medications like monoamine oxidase inhibitors may pose special risk when combined with Prozac®. Care must be taken when people take the medication with other drugs that can raise serotonin levels because this can risk serotonin syndrome, which creates toxic serotonin levels in the body.
When doctors prescribe this medication, patients should listen carefully to instructions. They should not stop or increase the dose except under a doctor’s guidance. Fluoxetine should also not be shared with others, and no one should take this medication unless a physician prescribes it.
An unusual syndrome associated with this medication is called “prozac poop—out.” This occurs after the medication has worked successfully for some time, but suddenly stops working. Actually, many medications may have a similar “poop-out” factor. It may mean that dose needs to be adjusted or that another SSRI will be more appropriate for treatment. Sometimes people are able to return to fluoxetine after taking a break from it by using another SSRI, and it becomes fully effective again.