Effects of a beta-blocker on the cardiovascular response to MDMA (Ecstasy).
MDMA (3,4-methylenedioxymethamphetamine, Ecstasy) produces tachycardia and hypertension and is rarely associated with cardiovascular and cerebrovascular complications. In clinical practice, beta-blockers are often withheld in patients with stimulant intoxication because they may increase hypertension and coronary artery vasospasm due to loss of beta(2)-mediated vasodilation and unopposed alpha-receptor activation. However, it is unknown whether beta-blockers affect the cardiovascular response to MDMA. The effects of the non-selective beta-blocker pindolol (20 mg) on the cardiovascular effects of MDMA (1.6 mgkg) were investigated in a double-blind placebo-controlled crossover study in 16 healthy subjects. Pindolol prevented MDMA-induced increases in heart rate. Peak values (mean-SD) for heart rate were 84-13 beatsmin after MDMA vs 69-7 beatsmin after pindolol-MDMA. In contrast, pindolol pretreatment had no effect on increases in mean arterial blood pressure (MAP) after MDMA. Peak MAP values were 115-11 mm Hg after MDMA vs 114-11 mm Hg after pindolol-MDMA. Pindolol did not change adverse effects of MDMA. The results of this study indicate that beta-blockers may prevent increases in heart rate but not hypertensive and adverse effects of MDMA.