Abstract
Sperm immobilizing activity of three class I antiarrhythmic drugs, quinidine, procainamide, mexiletine, one adrenoceptor blocking drug, labetalol and one calcium channel blocking drug, diltiazem was measured with a trans-membrane migration method. All these drugs immobilized human sperm. Local anaesthetic effect is the underlying mechanism for these drugs to inhibit sperm motility. Sperm immobilization could be a screening test for the local anaesthetic effect of antiarrhythmic drugs.