Atenolol is a selective beta blocker FDA-approved to treat hypertension; it is not approved for prevention of migraine. However, clinical trials suggest that it may be useful in the prevention of migraine. Occasionally this medicine may produce marked reduction in pulse rate and blood pressure, leading to lightheadedness. At low doses it may be safe for asthmatics and diabetics controlled with diet and oral medications. It usually takes at least four weeks to be effective.
Tenormin® and Tenoretic® are brand names of Atenolol.