How quickly does propranolol work?

When propranolol is used to relieve performance, social, or situational anxiety, it works quickly, usually within 30 to 60 minutes to help relieve physical symptoms of anxiety such as flushing, shaking, sweating, trembling, and an elevated heart rate. It is unlikely to relieve the mental symptoms of anxiety (such as mental fog or blankness), but generally relieving some of the physical symptoms improves the mental symptoms. Its effects last for 3 to 4 hours.

Propranolol may also be used for heart conditions such as high blood pressure or to slow the heart. Depending on the condition being treated, it usually starts to work in a few hours but may take up to a week to reach its full effect. Because high blood pressure often has no symptoms, you may not feel any different but that does not mean it is not working. Keep taking your medicine.

How quickly does propranolol work for migraines?

Propranolol is one of the most common and effective medications for preventing migraines – although it only reduces how often you get them, not their duration or severity. Because it is a preventive treatment, it needs to be taken regularly for an effect, and it may take up to 12 weeks before an effect is seen. The usual starting dose is 40 mg/day, but this can be increased to 320mg daily.