Assessment of sexual behaviour and fertility indices in male rabbits following chronic codeine use.

Abstract

Codeine is the latest trend of drug abuse, particularly in Nigeria and regarded as the gateway to the abuse of other substances. The present study examined the effects of graded doses of codeine on sexual behaviour and fertility profile. Rabbits were either administered normal saline (0.2mL), 4mg/kg b.w of codeine (low dose), or 10mg/kg b.w of codeine (high dose) p.o for 6weeks. Findings of the study showed that codeine administration significantly increased libido as witnessed by significantly short mount latency (ML), intromission latency (IL), post-ejaculatory interval (PEI) and significantly increased mount frequency (MF), intromission frequency (IF) and ejaculation latency (EL). Furthermore, codeine caused a marked rise in penile reflexes evident by a significant increase in erections, quick flips, long flips and total penile reflexes. However, copulatory efficiency and fertility index were significantly lower in codeine-treated groups when compared with the control. Serum levels of testosterone were also significantly lower in the treated groups. The present study demonstrates that codeine-induced enhancement of sexual performance is via a testosterone-independent mechanism. It also reveals that although codeine enhances copulatory locomotor activity, it is a potential risk factor for infertility.