Though there’s no cure for migraine, relief can be found in current drug treatments: acute for most patients and preventive for severe cases. Finding a medication that works and has tolerable side effects is a matter of trial and error’and patience. Research is gradually answering key questions about migraine, uncovering clues for potential treatments.
Short-term acute drugs
For many, the best available treatment to take when a migraine starts is a class of prescription drugs called triptans (there are seven in Canada in tablet, injectable and nasal-spray forms). Triptans are thought to constrict blood vessels, stopping them from releasing pro-inflammatory neuropeptides, cutting the migraine’s duration.
What you need to know: Triptans are no magic solution; you may need to try different ones before finding one that works. ‘They work well for more than half of migraine sufferers. In 30 to 40 percent, they work less well, and 15 percent do not respond at all,’ says Dr. Werner Becker, a neurologist and professor in the departments of clinical neurosciences and medicine in the University of Calgary’s faculty of medicine. For those in whom it works less well, doctors may combine triptans with other drugs, such as over-the-counter acetaminophen or ibuprofen. Because of their effect on blood vessels, triptans are not prescribed to people with coronary artery disease or uncontrolled high blood pressure. For severe cases, doctors may turn to preventive drugs (see below).
Future alternative: A newer class of drugs called CGRP (calcitonin gene-related peptide) antagonists could offer an alternative. While triptans are vascular constrictors (preventing the release of pain molecules), CGRP antagonists block a potential vasodilator pain transmitter in the first place. ‘The trials suggest they are as effective as triptans and should produce fewer side effects,’ says Becker. If the research continues to support the benefits, drugs could be available within two years.
Preventive medications are usually prescribed only to people who have severe or frequent migraine attacks, because they can come with some significant side effects.
What you need to know: Doctors turn to preventive drugs when acute medication is working, but the patient is still disabled (perhaps missing lots of work) and is taking acute medications too often. Too much acute medication can have a rebound effect, increasing the rate of migraine. Preventive options include:
‘ Antidepressants Serotonin, a neurotransmitter that causes blood vessels to constrict and reduces the release of other pain-relieving chemicals including dopamine, plays a major role in the brain’s pain perception. Tricyclic antidepressants seem to decrease pain by affecting the level of serotonin and other chemicals in the brain.
‘ Beta-blockers Used for heart conditions and high blood pressure, it is not yet clear why these medications are effective for migraines.
‘ Anti-seizure medications No one knows precisely how these medications prevent migraine, and they may cause side effects, such as nausea and hair loss.
‘ Oral contraceptives In specific cases, doctors will prescribe a continuous oral contraceptive to prevent estrogen fluctuations and stave off migraine. The downsides: It can take months to start working. Some women do not experience any changes in migraine, and a small percentage get more frequent episodes.
Future alternative: Early studies show that Botox might decrease chronic migraine pain. Researchers think it prevents the activation of pain nerve endings, and this in turn reduces pain perception in the brain. Botox is currently given ‘off label’ (when doctors prescribe a medication for a use not yet approved by Health Canada) for migraine. It’s injected into specific points in your scalp. The U.S. Food and Drug Administration recently approved it for migraines, and Canada may well follow suit.
This article was originally titled “Migraines Can Be Managed’ in the January/February 2011 issue of Best Health. Subscribe today to get the full Best Health experience’and never miss an issue!’and make sure to check out what’s new in the latest issue of Best Health