Betablockers are “Vasonormalizers” which prevent dilation and constriction of arteries. Adrenaline is made in two varieties: Alpha—which works on the lungs, and Beta—which works on arteries. Thus, the name Betablocker. The archetype Betablocker drug is Inderal, known generically as propranolol. This drug works to block some of the effects of adrenaline on arteries. It was the first drug approved by the Federal Drug Administration for the treatment of migraine in 1974 and is also used for other medical problems including: Migraine, Benign Essential Tremor, Hypertension, Angina (the chest pain heart patients get), and Cardiac Arrhythmias. It comes in a short term (4 hour lasting) dose or in LA (long acting-24 hour) form. Common doses are 80-320 mg/day. For younger patients with migraine or tremor the dose may be discontinued safely at a low dose such as 80 mg/day, while older patients with heart disease and higher doses should have the dose tapered slowly.
Inderal is usually well tolerated and has few side effects, although like all drugs it has two pages of small print listing possible side effects. The only potential side effect I warn patients about is that a small number of patients develop the so called “Inderal tired syndrome” after they start the drug, usually in the first week. If this side effect develops, then the drug should be stopped and another betablocker selected.
How long the drug has to be given is not known at the beginning and depends on the clinical indications. For tremor Inderal is usually given long term for years or life. For migraine I commonly encourage the patient to consider using the drug for 3-6 months at first, chart their headache numbers per month, and then reassess this on follow up. Many patients are able to get off the drug then although some patients with bad migraine are happy to continue.
Other Betablockers used for migraine prevention are: Corgard (naldolol), Tenormin (aetenolol), Lopressor (metoprolol), Timoptic (timolol), and Visken (pindolol).