It takes four weeks or more before steady levels are built up in the blood, and it may take as long for the drug to have an effect on depression. Fluoxetine accumulates in the body's tissues with prolonged use, and the drug may stay in the body for weeks or months after discontinuing therapy. It is especially important that at least five weeks pass after stopping the drug before starting another drug that may interact with fluoxetine. Fluoxetine has been studied in a number of small clinical trials in people with HIV infection. It general, it has been highly effective in reducing the symptoms of depression.
Fluoxetine is available as capsules for oral administration.
Treatment For depression, the recommended dose is 20 to 80 mg per day. As with all antidepressants, it is recommended that the lower dose be initially used and increased after several weeks as necessary if the person is not experiencing serious side effects. It may take up to four weeks to notice an effect. The dose may need to be reduced for people with poor liver or kidney function. For obsessive-compulsive disorder, the recommended treatment is 20 mg per day taken in the morning.