ABSTRACT

Prolactin is known to have significant immunomodulatory properties. Imipramine, a monoamine oxidase inhibitor, stimulates prolactin production because it decreases dopamine which inhibits secretion of prolactin. The study objective was to determine if use of imipramine can result in immunological benefits for HIV-positive patients by restoration and preservation of immunological function. A cohort of 19 retroviral positive patients was identified for the prospective study which continued for a 28-week period. Three patients dropped out before the study began. Inclusion criteria accepted only patients on the same highly active antiretroviral therapy (HAART) regimen for a nine-month period and who had reached a plateau with respect to the CD4 cell count and also had no prior history of antidepressant use for a 12-month period. This study had a “before and after” design, patients serving as their own control. The study drug imipramine was prescribed for a 12-week period up to visit 4, and then discontinued for 4-weeks (washout period) at which time blood investigations were done at visit 5. Finally, patients were prescribed the study drug for a further 12-week period to the end of the trial (visit 7). At the 95 per cent probability level, significant differences in average prolactin and CD4 levels from visit 4 to the end of the trial period were recorded. Results showed a trend of prolactin levels decreasing after washout (p = 0.015) and increasing by the end of the trial period once imipramine dispensation had recommenced (p = 0.006). With respect to the CD4 cell count, there was a significant increase after wash-out (p = 0.022). These results indicate a trend to immune boosting in HIV-positive patients who had obtained the maximum response from HAART.