Effect of short and long-term administration of lisuride in Cushing's disease

To define the role of dopaminergic drugs on pituitary ACTH secretion, we studied the effect of a dopamine-agonist, lisuride, on a group of 9 patients with pituitary dependent Cushing's syndrome. Lisuride (0.4-0.6 mg/day) was administered for two days: in only two out of eight cases the ACTH levels, sampled every 30 min for 6 h (08:00-14:00 h), showed some reduction when compared with the control day. Two of the nonresponders (R.P.; B.F.) and one untested patient (L.E.) were then treated chronically with a similar amount of lisuride per day for 20 days (L.E.) and for 4 months (B.F.; R.P.). One patient (L.E.) showed a clear decrease in urinary free cortisol without clinical improvement; while in the other two cases, followed for a longer period of time, a clinical improvement was observed together with a decrease of the hormonal parameters. In conclusion, lisuride may occasionally reduce ACTH secretion in patients with pituitary dependent Cushing's syndrome, but the acute test fails to identify the patients who would benefit from this treatment.