Decrease in erythrocyte:plasma lithium ratio by concurrent administration of psychotropic drugs and lithium in mice.
1. Previous studies paying attention to concurrent use of lithium (Li+) with a neuroleptic were not done under constant and controlled conditions. We were therefore encouraged to do a prospectively controlled study, presuming constant relevant factors, on concomitant use of Li+ with neuroleptic as well as other psychotropic agents. 2. The effects of concurrent administration of chlorpromazine, haloperidol, imipramine and carbamazepine with Li+ on the erythrocyte:plasma Li+ ratio and the intraerythrocyte Li+ concentration were studied in mice by using a new, direct method of measuring erythrocyte Li+ concentration. 3. All of the foregoing agents with the exception of carbamazepine were observed to significantly decrease the Li+ ratio. 4. Lack of any significant effect by carbamazepine on Li+ transport may be an indication of this drug's efficacy as a supplement in Li+ therapy of bipolar affective disorders. 5. The decrease in Li+ ratio observed with chlorpromazine, haloperidol and imipramine may be explained through the mechanism by which these drugs stabilize the cell membrane and consequently affect Li+ transport in erythrocytes. 6. Moreover, our study proves that, although the Li(+)-sodium countertransport mechanism does not exist in mice, the same interaction between Li+ and other psychotropic drugs is seen. It can be concluded that such interaction is not mediated through Li(+)-sodium countertransport. 7. It is suggested that, with concurrent use of a psychotropic drug and Li+, the amount of intraerythrocyte Li+ concentration be measured, instead of relying on the plasma Li+ concentration alone.
Sadeghipour-Roudsari
H R
HR
Department of Physiology, School of Medicine, Tehran University of Medical Sciences, Iran.
Farahani
M
M
Shokrgozar
A A
AA
Farsam
H
H
Dehpour
A R
AR
D000818:Animals; D014150:Antipsychotic Agents / Q000097:blood / Q000494:pharmacology*; D002220:Carbamazepine / Q000494:pharmacology; D002746:Chlorpromazine / Q000494:pharmacology; D004359:Drug Therapy, Combination; D004912:Erythrocytes / Q000187:drug effects*; D006220:Haloperidol / Q000494:pharmacology; D007099:Imipramine / Q000494:pharmacology; D008094:Lithium / Q000097:blood / Q000494:pharmacology*; D008297:Male; D051379:Mice; D011446:Prospective Studies
D014150:Antipsychotic Agents; D002220:Carbamazepine; D008094:Lithium; D006220:Haloperidol; D007099:Imipramine; D002746:Chlorpromazine