A new study has found that almost all blood-pressure-lowering medications reduce the number of headaches migraine sufferers have each month. The researchers say that these medications may provide a treatment option that is less expensive and more accessible than available migraine medications.

A throbbing, pulsing headache is a common symptom of migraines. But it’s much more than a bad headache; migraines can cause debilitating pain and sensitivity to light, sound or smells, interfering with a person’s ability to function. The symptoms are changeable, as is the severity of the pain, and migraine is estimated to affect around 15% of the world’s population.

Migraine medications are designed to stop symptoms and prevent future attacks, but they can be expensive. In 2020 in the US, the cost of migraine treatment ranged from US$2,000 to over $9,000 per person per year and may not have been covered by insurance. Blood-pressure-lowering medications, known as antihypertensives, are sometimes prescribed as a preventative to reduce how often migraines occur and the length and severity of headaches. Current prescribing guidelines recommend a couple of classes of blood pressure (BP) medications, beta-blockers (BB) and angiotensin II receptor blockers (ARB), for treating migraines.

A new study by researchers at The George Institute for Global Health in Sydney, Australia, has found that almost all classes of antihypertensives have some ability to reduce the frequency of headaches in migraine sufferers.

“For countries where new migraine medications are expensive, limited by prescribing criteria or not available at all – covering all countries to some extent – this study shows that common BP medicines, which GPs are comfortable prescribing, can be an important preventative measure for patients with migraine or severe headache episodes,” said Cheryl Carcel, lead author of the study.

The researchers performed a meta-analysis of all randomized trials of antihypertensives on the prevention of episodic migraine, defined as less than 15 headache days per month. The analysis included 50 trials and 4,310 participants. They looked at the effectiveness of BB and ARB in addition to alpha-blockers (AB), angiotensin-converting enzyme inhibitors (ACEi), and calcium channel blockers (CCB), compared to a placebo.

Before we get into the study’s findings, here’s a quick rundown of how each class reduces BP without going into its physiological effects in great detail, along with some common brand names. Beta-blockers (e.g., Tenormin, Lopressor, Toprol, Levatol) lower heart rate and the heart’s output. ACEi (Capoten, Monopril, Accupril, Lotensin) reduce the production of angiotensin, which helps the blood vessels relax and dilate. ARB (Atacand, Micardis, Avapro) block the effect of angiotensin, producing a similar result to ACEi. CCB (Norvasc, Plendil, Adalat) stops calcium from entering the muscle cells of the heart and arteries, dilating narrowed blood vessels and reducing heart rate. AB relaxes the muscle tone of the arteries, reducing their resistance.

The researchers found that for each class of drug, there was a lower number of headache days per month compared to a placebo, except for those taking ACEi or a combination of antihypertensives. The greatest reduction in monthly headache days was seen with CCB. On average, antihypertensives reduced the number of headache days per month by about one day on top of the average placebo effect.

The researchers say their findings are “clinically relevant,” given the lower cost and availability of antihypertensives, health insurance coverage, and the incidence of side effects. Common side effects of migraine medications include weight gain and drowsiness.

“Around 90% of people with migraine can be managed in general practice, where the goal is to prevent as many episodes as possible because of the disabling impact they have on the patient’s quality of life,” said Faraidoon Haghdoost, one of the study’s co-authors. “The good news is that blood pressure medications are widely available at low cost, with many available in generic forms, presenting a trusted treatment option alongside other preventive measures such as avoiding triggers and making lifestyle changes.”

The researchers plan to undertake a further review to provide more information about the particular antihypertensive drugs that work best to combat the headaches associated with migraine.

The study was published in the journal Cephalalgia.

Source: The George Institute for Global Health