The influence of the route of administration of imipramine on imipramine and desipramine blood levels.

Imipramine was used to treat 18 depressed inpatients for 22 days. Imipramine 2 mg/kg/day was administered from day 0 to day 14 intramuscularly, and 4 mg/kg/day was administered orally from days 15-21. Two pharmacokinetic studies were performed, the first at the end of the intramuscular phase (day 14) and the second at the end of the oral phase (day 21).