Fluoxetine (Prozac) is used to treat depression, obsessive-compulsive disorder (bothersome thoughts that won't go away and the need to perform certain actions over and over), some eating disorders, and panic attacks (sudden, unexpected attacks of extreme fear and worry about these attacks). Fluoxetine (Sarafem) is used to relieve the symptoms of premenstrual dysphoric disorder, including mood swings, irritability, bloating, and breast tenderness. It works by increasing the amount of serotonin, a natural substance in the brain that helps maintain mental balance.

Fluoxetine is also sometimes used to treat alcoholism, attention-deficit disorder, borderline personality disorder, sleep disorders, headaches, mental illness, posttraumatic stress disorder, Tourette's syndrome, obesity, sexual problems, and phobias. Talk to your doctor about the possible risks of using this medication for your condition.

Special precautions

Before taking fluoxetine,

• Tell your doctor and pharmacist if you are allergic to fluoxetine or any other medicines.
• Tell your doctor and pharmacist if you are taking vitamins, nutritional supplements, and herbal products.
• tell your doctor if you have or have ever had, or anyone in your family has or has ever had, depression, bipolar disorder (mood that changes from depressed to abnormally excited), or mania (frenzied, abnormally excited mood), or you have, or anyone in your family has, thought about or attempted suicide. Also tell your doctor if you have recently had a heart attack and if you have or have ever had diabetes, seizures, or liver or heart disease.
• Tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking fluoxetine, call your doctor.
• You should know that fluoxetine may make you drowsy. Do not drive a car or operate machinery until you know how this medication affects you.
• Remember that alcohol can add to the drowsiness caused by this medication.
• You should know that your mental health may change in unexpected ways, especially at the beginning of your treatment and at any time your dose is increased or decreased.

Side effects

Fluoxetine may cause side effects:

• nervousness
• difficulty falling asleep or staying asleep
• upset stomach
• dry mouth
• sore throat
• drowsiness
• weakness
• shaking hands that you cannot control
• loss of appetite
• weight loss
• changes in sex drive or ability
• excessive sweating

Some side effects can be serious. The following symptoms are uncommon:

• skin rash
• hives
• fever
• joint pain
• swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
• difficulty breathing or swallowing
• seeing things or hearing voices that do not exist (hallucinating)
• seizure

Fluoxetine may cause other side effects. Call your doctor if you have any unusual problems while taking this medication.

Symptoms of overdose may include:

• unsteadiness
• confusion
• unresponsiveness
• nervousness
• shaking hands that you cannot control
• dizziness
• rapid, irregular, or pounding heartbeat
• seeing things or hearing voices that do not exist (hallucinating)
• fever
• fainting
• coma

Keep all appointments with your doctor.