Summary: It has long been known that some drugs may cause headaches resembling migraines or cluster headaches. Even abusing painkillers like NSAIDs and opioids may cause headaches. Now a new study has looked at the US FDA adverse event reporting system data. It found that immunosuppressants and immunomodulators also commonly cause headaches. These are drugs that calm or adjust the immune system.
People rarely blame their headaches on the very medicine meant to relieve pain. Yet studies show that many common pain drugs may become the source of headaches. Many of these drugs treat inflammation and chronic pain. They might cause headaches that closely resemble migraine or cluster headaches. So if you live with chronic pain or headaches, you need to know which drugs are often linked to headaches.
Early studies have shown that abusing painkillers may cause headaches. In fact, almost all painkillers, if abused, may increase pain sensation and cause headaches. People who abuse NSAIDs, acetaminophen, opioids, and other analgesics are more likely to suffer from chronic migraine disorder. The risk is very high in people who use these drugs 10-15 days a month for more than three months.
But new studies suggest the problem is worse than anyone thought. Even some newer drugs for inflammation, chronic pain, and autoimmune disorders may cause headaches. Take monoclonal antibodies, immunomodulators, antivirals, and pulmonary artery dilators. These are commonly linked to chronic headaches. This new study was presented at the annual meeting of the American Headache Society.
For the study, the team looked at US FDA data on the side effects of many drugs. The database also records side effects reported by clinicians. The researchers were quite surprised by how often immunosuppressants and immunomodulators were linked to headaches.
People often need these drugs for severe health problems. Many must take them regularly. Quite often, switching to another drug is not an option. And the study only looked at side effects that got reported. Many cases never get reported. So the real risk of headaches from these drugs might be much higher.
Researchers also found that some drugs in this same class were much less likely to cause headaches. That puzzled them. It is hard to explain why some drugs in one class cause headaches and others do not. The team used US FDA adverse event reporting system data. They studied headache reports tied to drugs from 2018 to 2020. It is a pharmacovigilance database (a drug safety log). Doctors or patients may report side effects they had from approved drugs.
Headaches were common with apremilast, with 8,672 reports. Other immune drugs often linked to headaches were adalimumab (5,357), tofacitinib (4,276), fingolimod (4,123), and etanercept (4,111). These drugs often treat psoriasis, inflammatory bowel disease, and multiple sclerosis. These conditions are hard to treat. There are few other options. So changing the drug is often off the table.
Other drugs linked to headaches were those for hepatitis C, pulmonary hypertension, arthritis, and asthma. For some drugs, such as those for pulmonary hypertension, the reason is simple. Those drugs are also likely to act on other blood vessels, and that causes headaches. But researchers still cannot explain why many of the other drugs cause headaches.
The team admits this is not the best way to judge a drug’s side effects. Many of these reports came from individual people. They are not findings from clinical studies. Data sets like this do not give highly reliable information. Still, the researchers say the findings are suggestive, and these issues need more scientific study.
Frequently asked questions
Which medications are most often linked to headaches?
In US FDA adverse event reports from 2018 to 2020, drugs that act on the immune system led the list. Apremilast had 8,672 headache reports. Next came adalimumab, tofacitinib, fingolimod and etanercept. These drugs treat psoriasis, inflammatory bowel disease and multiple sclerosis. Drugs for hepatitis C, pulmonary hypertension, arthritis and asthma were also commonly linked to headaches.
Can pain relievers cause headaches?
Yes. Almost any painkiller, used too often, can make you more sensitive to pain and cause headaches. People who overuse NSAIDs, acetaminophen, opioids and other analgesics are more likely to develop chronic migraine. The risk is especially high when these drugs are taken 10 to 15 days a month for more than three months. Many people never suspect the medicine they take for pain.
Why do some medications cause headaches?
For some drugs the reason is clear. Drugs for pulmonary hypertension also act on other blood vessels. That can trigger headaches. For many others, researchers still cannot explain why. That includes drugs in the same class where one causes headaches and another rarely does. That puzzle is one reason these findings need more study.
Should I switch a medication that gives me headaches?
Often that is not simple. Many of these drugs treat serious, hard-to-treat conditions with few other choices. People need to take them regularly. The same study did find that some drugs in the same class were much less likely to cause headaches. If your headaches started with a new medicine, bring that pattern to the doctor who manages your treatment.
How reliable is the FDA data on headache side effects?
It is suggestive, not proof. The FDA system collects side effects reported by doctors and patients. These are not results from clinical studies, so they cannot give highly reliable numbers. The system also misses cases. Many side effects never get reported. So the real risk of headaches from these drugs may be much higher than the reports show.
Padda Institute of Pain Management is one of the renowned pain treatment centers in St. Louis that offers the best medication for various types of headaches. The experts at Padda Institute provide headache treatments that are unique to a person’s needs. Schedule your appointment today!
Dr. Gurpreet Singh Padda, MD, MBA, MHP
