Effect of cannabidiol on plasma prolactin, growth hormone and cortisol in human volunteers

RESUMO

In the present study, we investigated the effects of cannabidiol (CBD) on plasma prolactin, growth hormone and cortisol of 11 normal volunteers who received placebo or CBD at the doses of 300 mg (N = 7) or 600 mg (N = 4), po, in a double-blind manner during two experimental sessions separated by an interval of at least one week. The sessions were held in the morning and consisted of blood collection and application of self-evaluation scales before and after drug injection (-35 to 180 min). Hormonal measurements were performed by radioimmunoassay. Basal prolactin (11.5 +/- 4.3 ng/ml) and growth hormone (1.5 +/- 0.7 ng/ml) levels were unchanged after placebo and CBD. In contrast, plasma cortisol levels decreased significantly during the placebo sessions (basal measurement = 11.0 +/- 3.7 micrograms/dl; 120 min after placebo = 7.1 +/- 3.9 micrograms/dl), in agreement with the normal circadian rhythm of this hormone. This decrease in cortisol levels was significantly attenuated after CBD (basal measurement = 10.5 +/- 4.9 micrograms/dl; 120 min after 300 mg CBD = 9.9 +/- 6.2 micrograms/dl; 120 min after 600 mg CBD = 11.6 +/- 11.6 micrograms/dl). CBD was also found to have a sedative effect as determined by the self-evaluation scales. The present results suggest that CBD interferes with cortisol secretion