Fluoxetine hydrochloride (HCl) is an antidepressant medication which belongs to the class of drugs known as selective serotonin reuptake inhibitors (SSRIs). Development of this medication dates to the 1970s, with Eli Lilly's Prozac® being the most famous brand name that fluoxetine HCl is sold under. Unless specifically directed otherwise, a pharmacist will fill a prescription for this medication with the generic version of the drug, rather than a branded one, because generics are much less expensive.

This drug is designed to change the chemistry of the brain to help patients with conditions such as depression, bulimia, panic disorders, and obsessive compulsive disorder. Like other antidepressants, fluoxetine HCl usually takes several weeks to take effect, and the dosage often needs to be adjusted to meet the patient's needs. Doctors usually ask patients to try an introductory dosage for four weeks, and then return for a follow up visit to see how effective the drug is for the patient, and whether or not the dosage needs to be altered. The patient will require periodic visits for psychotherapy and adjustments of the dosage as needed as long as he or she remains on the drug.

Certain medications can interact adversely with fluoxetine HCl, making it important for patients to disclose all of the medications they are taking, including non-prescription drugs, when discussing this drug with their doctors. The drug can also be dangerous for people with liver impairments, and these patients require special monitoring. Side effects associated with fluoxetine HCl include anorexia, anxiety, sleeplessness, tremors, and sexual dysfunction.

Studies on this drug have suggested that when patients stop taking it, it is important to taper the dosage, rather than abruptly ceasing treatment. Patients can experience psychological problems if they abruptly stop taking fluoxetine HCl or if the dosage is adjusted too rapidly. Patients can taper off the drug under the supervision of a physician who can confirm that the patient is being safely weaned from the drug. Patients who have difficulty affording medications can experience problems as a result of stopping and starting treatment or suddenly ceasing treatment.

Several formats of fluoxetine HCl are available to patients, including time-released versions which need to be taken less frequently. Although originally only available as a brand name medication, the drug is now available in generic format. The generic format is pharmacologically identical to the brand name drug, and typically less costly. Due to concerns about how the drug is used and the need for supervision, fluoxetine HCl is not available over the counter to patients.