A blood pressure medication telmisartan (Micardis) was shown to be effective in the prevention of migraine headaches by a group of German researchers led by H-C Diener.  Several blood pressure medications have been proven to prevent migraine headaches.  The oldest category of blood pressure drugs, beta-blockers have the most evidence to support their use and two of them (propranolol and timolol) are approved by the FDA for the preventive treatment of migraines.  However, beta-blockers are not high on my list because they tend to cause more side effects than other blood pressure medications.  The most common side effects are due to excessive lowering of blood pressure – lightheadedness, fatigue, and fainting.  They also slow down the heart rate, which can make it difficult to exercise, while regular aerobic exercise is the first treatment I recommend to my headache patients.  Calcium channel blockers, such as verapamil, are not as effective for migraine prevention as they are for the prevention of cluster headaches and can cause constipation, swelling and irregular heart beats.  Another blood pressure medication, lisinopril which belong to the family of ACE inhibitors has also been shown to prevent migraine headaches.  The most common limiting side effect of ACE inhibitors is coughing.  A newer group of medications, which are similar in action to ACE inhibitors is ACE receptor blockers, or ARBs.  ARBs do not cause coughing and telmisartan which is one of the ARBs caused as few side effects as the placebo.