PHILADELPHIA – Analgesic and triptan use should be restricted to no more than 10–12 doses a month to prevent patients with episodic migraine or tension type headaches from developing a chronic condition, Volker Limmroth, M.D., Ph.D., reported at the annual meeting of the American Headache Society.
The prevalence of medication-overuse headache (MOH) is approximately 1% in the general global population, said Dr. Limmroth of the department of neurology at the University Hospital in Essen, Germany. He based his estimate on a wide range of epidemiologic studies from around the world.
Before 2003, when the International Classification of Headache Disorders was updated, the definition of MOH (formerly called drug-induced headache), did not cover all available agents, especially not modern antimigraine drugs such as triptans, Dr. Limmroth said.
Now, according to the International Classification of Headache Disorders, second edition, MOH is defined as a headache on 15 or more days a month, with drug intake of ergots, triptansm, or opioids for 10 or more days per month for a minimum of 3 months, or with use of analgesics for 15 or more days per month for a minimum of 3 months. In addition, the chronic headache would disappear or revert to its previous pattern by 2 months after withdrawal.
Based on the new classification, the German Society for Neurology has already issued guidelines limiting the intake of triptans and analgesics to 10 doses per month, Dr. Limmroth said in an interview with this newspaper.
To treat MOH patients who are overusing triptans or analgesics, Dr. Limmroth strongly recommended inpatient withdrawal. “It's important for doctors to realize that the length of time it takes for successful withdrawal is different, depending on the primary headache [whether migraine or tension-type headache] and the medication used,” Dr. Limmroth said. Following withdrawal therapy, patients go back to the number of episodic headaches they had before medication overuse, he said.
Withdrawal symptoms vary according to the drug that has been overused. After withdrawal from triptans, withdrawal symptoms last about 4 days on average. With ergots, they can last up to 7 days. Withdrawal from analgesics can take longer, and even after 2 weeks, 70%–80% of headaches can persist, he said. It is very important to be aware of these variations and to follow patients for a long enough time to ensure successful withdrawal.
“If withdrawal is done correctly, about 60% of the patients with chronic conditions get better and stay better for years,” Dr. Limmroth said.
Nevertheless, relapse is a problem with medication overuse. Overall, including all types of headache medications (triptans, ergots, and analgesics), studies found that about 28% of patients went back to overuse 6 months after withdrawal; 35%, after 1 year; and 42%, after 4 years, Dr. Limmroth said. Relapse is more common with tension-type headaches than with migraines, he added.
“Doctors who treat patients with chronic migraine and MOH need to look very closely within the first year after withdrawal to see whether the frequency of headaches requires preventive treatment,” he said. “Patients should be put on an individualized medication regimen, which they can comply with and tolerate, to prevent the headaches and also to prevent a relapse of overuse,” he said.