As of 2015, numerous patients have used fluoxetine, marketed as Prozac, without experiencing long-term side effects, and physicians prescribe it for extended periods, according to Everyday Health. Weight and sleep changes and sexual dysfunction are among fluoxetine's short-term side effects. Sexual side effects that occur during early use, such as ejaculatory delay or orgasm problems, frequently do not decrease with time, according to the National Alliance on Mental Illness.
Patients taking fluoxetine may experience side effects including headache, nausea, diarrhea, insomnia and nervousness, explains the National Alliance on Mental Illness. The symptoms typically lessen about two weeks after patients begin to take the medication. Patients with seizure disorders or histories of heart, liver or kidney diseases should exercise caution when taking fluoxetine, explains Everyday Health.
Even when patients feel better, they should continue to take fluoxetine and consult their doctors about their treatment lengths, according to the National Alliance on Mental Illness. If patients want to stop taking the drug after long-term use, they need to reduce their doses slowly to avoid experiencing withdrawal symptoms, notes Everyday Health.
Fluoxetine increases the level of serotonin in the brain, explains Everyday Health. Physicians prescribe the drug to treat depression, binge eating, obsessive-compulsive disorder, panic disorder and bulimia. Doctors also prescribe fluoxetine, marketed as Sarafem, for women who are depressed, irritable and tense before menstruation, a condition called premenstrual dysphoric disorder.