The effect of proadifen, a drug metabolism inhibitor, on action of imipramine and desipramine in mice.

Proadifen (SKF 524 A) inhibited the following effects of imipramine (IMI), without affecting those of desipramine (DMI) in mice: antagonism towards reserpine-induced hypothermia, ptosis and sedation, antagonism to apomorphine hypothermia and insignificant shortening of the immobility time in the behavioral despair test. Cerebral levels of DMI were very low after administration of IMI; pretreatment with proadifen did not affect the already low levels of DMI but significantly elevated these of IMI. This may indicate that some other than DMI metabolites (e.g., 2-hydroxy-derivatives) may be of importance for the action of IMI in mice in the tests employed in this study.