Effects of separate and combined chronic ingestion of promethazine and haloperidol on learning behaviour among female Wister albino rats
Keywords:Haloperidol, promethazine, learning behaviour, female albino rats
Increase in the use of neuroleptic medications and reported discrepancies in their effects on cognitive and psychomotor function are a research concern. Haloperidol and promethazine are used commonly and are among the over-the-counter prescribed drugs in Nigeria. This study examined the effects of chronic administration of haloperidol and promethazine on spatial learning behavior and memory among female albino rats. A total of 24 female Albino rats weighing between 180 to 200g were randomly assigned into four groups of control containing 6 rats each. Promethazine, haloperidol and promethazine combined with haloperidol, were used for this study. The rats were exposed to chronic treatment of haloperidol and promethazine at doses of 1mg/kg and 1.1mg/kg bodyweight respectively for 28 days and run on the Y-Maze for spatial learning and memory on each day of the experiment. Promethazine did not significantly affect spatial learning behavior and memory of female Albino Rats F (1, 332) = .13, p > 0.05, η2= .00 as well as haloperidol F (1, 332) = 53, p > 0.05, η2= .00. Combined treatment of haloperidol and promethazine significantly affected spatial learning behavior and memory among the female albino rats F (1, 332) = 4.58, p < 0.05, η2= .02. Female albino rats in the control ( 148.24) had slower learning time compared to female rats ingested with a combination haloperidol and Promethazine ( 118.01). It is concluded that combined treatment of haloperidol and promethazine significantly affected learning behaviour but none with separate treatment. The dose of exposure of the haloperidol and promethazine should be studied further to establish the memory and learning deficit claims for the drugs.