Clinical Pearls on Prozac (Fluoxetine)

• Prozac is primarily prescribed for Major Depressive Disorder (MDD), Obsessive-Compulsive Disorder (OCD), Bulimia Nervosa, and Panic Disorder.

• It is also used off-label for conditions like Premenstrual Dysphoric Disorder (PMDD), Body Dysmorphic Disorder, and anxiety disorders.

• Initiate treatment with lower doses and gradually increase to gauge therapeutic response and minimize side effects. Typical starting dose for adults in depression is 20 mg daily.

• Dosage adjustments should be made cautiously and not more frequently than once a week due to the drug’s long half-life.

• Prozac has a long half-life (4-6 days) and its active metabolite, norfluoxetine, has an even longer half-life (4-16 days). This means it could take several weeks to achieve steady-state plasma levels.

• Its long half-life can be an advantage for patients with compliance issues but also means that side effects or adverse reactions could be prolonged.

• Prozac is a potent inhibitor of CYP2D6, which can lead to significant drug-drug interactions. Caution is necessary with drugs metabolized by this pathway, such as certain beta-blockers, antiarrhythmics, and antipsychotics.

• Combining SSRIs like Prozac with MAOIs or other serotonergic drugs increases the risk of serotonin syndrome, a potentially life-threatening condition.

• Common side effects include nausea, headache, anxiety, insomnia, drowsiness, and sexual dysfunction. Educating patients about these potential effects is crucial for adherence.

• Weight changes and potential for increased suicide risk, especially in young adults and adolescents, should be closely monitored.

• Prozac is classified as FDA pregnancy category C. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

• The drug is excreted in breast milk, so caution is advised when prescribing to breastfeeding women.

• Abrupt discontinuation should be avoided to prevent withdrawal symptoms such as mood changes, irritability, agitation, dizziness, sensory disturbances, and confusion.

• Tapering the dose slowly is recommended when discontinuing treatment.

• Educate patients on the importance of adherence and consistent medication use, despite a delayed onset of antidepressant action, which can take several weeks.

• Inform patients about the importance of not overusing or abruptly stopping the drug, and advising them to discuss any concerns with their healthcare provider to optimize treatment.