Tatyana A. Shamliyan, MD, from the University of Minnesota, in Minneapolis, and colleagues conducted a literature review to identify randomized controlled trials (RCTs) of preventive drugs versus placebo or active treatments examining rates of ≥50 percent reduction in monthly migraine frequency or improvement in quality of life.
Based on 215 published RCTs, the researchers found that placebo was outperformed by all approved drugs, including topiramate (nine RCTs), divalproex (three RCTs), timolol (three RCTs), and propranolol (four RCTs); off-label beta blockers metoprolol (four RCTs), atenolol (one RCT), nadolol (one RCT), and acebutolol (one RCT); angiotensin-converting enzyme inhibitors captopril (one RCT) and lisinopril (one RCT); and angiotensin II receptor blocker candesartan (one RCT), in reducing monthly migraine frequency by 50 percent or more in 200 to 400 patients per 1,000 treated. Topiramate, off-label antiepileptics, and antidepressants had higher levels of adverse events, leading to treatment discontinuation. While there were no statistically significant differences in benefits between approved drugs, off-label angiotensin-inhibiting drugs and beta-blockers were the most effective and tolerable for episodic migraine prevention.
"Evidence is lacking for long-term effects of drug treatments (i.e., trials of more than three months duration), especially for quality of life," the authors write.