Background

Fluoxetine hydrochloride (brand names include Prozac®, Symbyax® (compounded with olanzapine), Sarafem®, Fontex® (Sweden), Fluctine (Austria, Germany), Prodep (India), Fludac (India) is an antidepressant drug used medically in the treatment of depression, obsessive-compulsive disorder, bulimia nervosa, premenstrual dysphoric disorder, and many other disorders. It is a selective serotonin reuptake inhibitor (SSRI), and is marketed in capsules containing 10, 20, 40 or 60 mg of active ingredient, in tablets containing 10 mg, or in a oral solution with concentration of 5 mg/5 ml (?). Dosages in the range of 20-60 mg per day are standard, with 80 mg considered a maximum. Eli Lilly's Prozac was approved by the FDA on December 27, 1987 and introduced in the US at the beginning of 1988. The drug became very popular, with millions around the world having taken the medication. In Fall 2001, Eli Lilly lost a patent dispute with Barr Laboratories and now Fluoxetine HCl is manufactured by many companies.

Fluoxetine has a wide range of published interactions, notably with monoamine oxidase inhibitors. Common side-effects include anxiety, restlessness, trembling, weakness, skin rash, anorgasmia, itching, and a decrease in sexual drive.

Fluoxetine is eliminated very slowly by the body. The half-life of fluoxetine after a single dose is two days and, after multiple dosing, four days. The liver then metabolizes fluoxetine into norfluoxetine, a desmethyl metabolite, which is also a serotonin reuptake inhibitor; norfluoxetine has an even longer half-life, i.e. 8.6 and 9.3 days for single and repeated dosage respectively. Other SSRIs have, by comparison, a very short half-life - some professionals feel that it is fluoxetine's long half-life that gives it much of its therapeutic utility. Fluoxetine is a potent CYP2D6 inhibitor, which can decrease metabolism of other medications.

In December 2003 the FDA approved Symbyax to treat bipolar depression. Symbyax is a combination of fluoxetine and olanzapine.

Controversy

In the late 1990s, a backlash grew against Prozac®. Prozac®'s manufacturer, Eli Lilly and Company, earned billions from its success, and became the target of numerous accusations (see David Healy affair). Lawsuits amounting to millions were instigated, alleging the drug made users feel suicidal and/or caused other serious side effects. The accusations and lawsuits have been unsuccessful in stemming the prescription and use of the medication, as well as in making the accusers some of Lilly's profits. Recently, the US FDA considered similar controversial issues regarding Prozac® and its use in children and adolescents; it issued a "black box warning" (its most serious warning) for Prozac® and other antidepressants (SSRI's and antidepressants of related classes) due to findings of increased suicidality in some children and adolescents on the drugs.

A more recent controversy embroiled Lilly, and a class action lawsuit has been filed after several people received in the mail free samples of Prozac® Weekly™. The suit alleges that the samples' recipients' right to privacy was mishandled.

In August 2004 a report by the Environment Agency found trace amouts of fluoxetine in UK drinking water, although the Drinking Water Inspectorate said that it was unlikely to pose a health risk. However, the effects from ingestion of fluoxetine in drinking water has not been investigated.

In January, 2005, the British Medical Journal was leaked official Eli Lilly documents from the 1980s suggesting the a link between fluoextine and suicide and psychosis. It was originally claimed that the documents had not been previously disclosed, and they were subsequently provided to the FDA for further investigation. However, Eli Lilly later claimed that the documents had been released in earlier litigation.[1] The British Medical Journal ultimately retracted its claim that the documents had not been previously disclosed, and apologized to Eli Lilly.[2]

The resources at the end of this article present a blend of views on this drug, some of which focus on the more controversial and unscientific issues.

External links

• Producer of Prozac®, Eli Lilly and Company, Inc.
• Lilly's Prozac® advertising website
  
• Prozac Truth, The Untold Story
• Side Effects
• Open Directory Fluoxetine
• Prozac Information
• BBC report on Prozac in drinking water