Propranolol, sold under the brand name Inderal among others, is a medication of the beta blocker class. It is used to treat high blood pressure, a number of types of irregular heart rate, thyrotoxicosis, capillary hemangiomas, performance anxiety, and essential tremors, as well to prevent migraine headaches, and to prevent further heart problems in those with angina or previous heart attacks. It can be taken by mouth or by injection into a vein. The formulation that is taken by mouth comes in short-acting and long-acting versions. Propranolol appears in the blood after 30 minutes and has a maximum effect between 60 and 90 minutes when taken by mouth.