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Prozac is an SSRI antidepressant used to treat chemical imbalance and other indications. The drug may increase the risk of developing serotonin syndrome or other side effects. Taking Prozac during pregnancy may result in birth defects.

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Prozac (fluoxetine hydrochloride) is an oral antidepressant prescription medication used to treat several conditions such as major depressive disorder, obsessive compulsive disorder, bulimia nervosa, and panic disorder. Prozac affects levels of certain chemicals in the brain known as serotonin that may become unbalanced causing depression, anxiety, panic, and obsessive compulsive symptoms.

Prozac and Serotonin Levels

Prozac is a member of the selective serotonin reuptake inhibitors (SSRIs), one of several different classes of antidepressant drugs. These drugs work to increase the levels of serotonin, a neurotransmitter that is generally associated with mood and overall well-being, and helps maintain a mental balance. 1 Other members of this class include Zoloft (sertraline, Pfizer), Celexa (citalopram, Forest Laboratories), and Paxil (paroxetine, GlaxoSmithKline).

Fluoxetine Indications

Prozac may be taken alone or as a combination therapy with olanzapine under the brand name Symbyax in variable doses. Fluoxetine, the generic name of Prozac, may also go under different brand names such as Rapiflux, Sarafem, and Selfemra. This may differ depending on the market and manufacturer. With all drugs, if you are unsure whether you are receiving the correct medication, consult your physician or pharmacist to confirm the proper appearance, dose, and drug you are receiving.

Prozac has also been used in the treatment of other conditions that are referred to as “off-label.” Although the drug lacks specific labeling for these indications, use is supported by clinical evidence and information in the medical literature.

Prozac is indicated in the treatment of conditions such as Major Depressive Disorder, Obsessive Compulsive Disorder, Bulimia Nervosa, and Panic Disorder. Prozac is also available as a combination drug with olanzapine and is indicated in the treatment of Depressive Episodes Associated with Bipolar I Disorder and Treatment Resistant Depression (i.e., patients who do not respond to two separate trials of different antidepressants).

Other Uses (Off-Label)

Prozac has also been used in the treatment of other conditions that are referred to as “off-label.” Although the drug lacks specific labeling for these indications, use is supported by clinical evidence and information in the medical literature. These conditions include: alcoholism, attention-deficit disorder, borderline personality disorder, sleep disorders, headaches, mental illness, post-traumatic stress disorder, Tourette’s syndrome, obesity, sexual problems, and phobias.

Serotonin Syndrome and MAOIs

This potentially life-threatening condition occurs when there is an excess level of serotonin activity.

Patients who are allergic or who have a hypersensitivity to Prozac should avoid using the antidepressant. Also, you should avoid Prozac if you are currently taking other antidepressants known as monoamine oxidase inhibitors (MAOIs), due to the risk of developing serotonin syndrome. The use of MAOIs with Prozac or within five weeks of stopping Prozac should be avoided. Do not take Prozac if you take the antipsychotic medicine pimozide (Orap) due to the potential development of heart problems. The use of thioridazine (Mellaril) is also contraindicated within five weeks of when stopping Prozac treatment.

Prozac Dosing

When prescribing Prozac, the dose of the medication can depend on a number of factors including sex, weight, and ethnicity. Patient variability along with difference in the patient’s overall response to the drug will require dose adjustments. The recommend starting dose for some indications are as follows:

Disorder Recommended Starting Dosage
Major Depressive Disorder 20 mg/day in adults; 10 mg/day in younger patients
Obsessive Compulsive Disorder 20 mg/day in adults; 10 mg/day in younger patients
Bulimia Nervosa 60 mg/day in the morning
Panic Disorder 10 mg/day

Dosage adjustments, if indicated, should be made with the individual components according to efficacy and tolerability. The treatment of Depressive Episodes associated with Bipolar I Disorder or treatment resistant depression with fluoxetine alone is not suggested. Talk to your doctor for more information and to verify you are taking the right dosage.

Side Effects of Prozac

Due to the complexity of this drug and how it works, patients are routinely monitored for side effects and adverse reactions. They may also depend on various patient characteristics (age, weight, sex, ethnicity, etc.) and can range in severity from very minor or common side effects to more severe or major events that can be life-threatening and require immediate medical attention. Taking Prozac as prescribed is important to reduce these risks.

Common Side Effects

  • Nervousness
  • Nausea
  • Dry mouth
  • Sore throat
  • Drowsiness
  • Weakness
  • Uncontrollable shaking
  • Difficulty sleeping
  • Strange dreams
  • Loss of appetite
  • Weight loss
  • Changes in sex drive or ability
  • Excessive sweating

More Serious Side Effects

  • Rash
  • Hives
  • Fever
  • Joint pain
  • Swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
  • Difficulty breathing or swallowing
  • Fever
  • Sweating
  • Confusion
  • Fast or irregular heartbeat
  • Severe muscle stiffness
  • Seeing things or hearing voices that do not exist (hallucinating)
  • Seizures

This is only a few of the symptoms that have been reported. Talk to your healthcare professional about other possible side effects or if you experience any new or worsening symptoms.

  1. Journal of Psychiatry & Neuroscience. 2007 November; 32(6): 394–399