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. However, a new study that analyzed the US FDA adverse event reporting system data found that immunosuppressants and immunomodulators also commonly cause headaches.
People are least likely to associate their headaches with medications that are intended to provide pain relief. However, studies show that many commonly used drugs to treat different pain conditions may become the source of headaches. Many of these drugs are used to treat inflammatory conditions and chronic pain. They might cause headaches that closely resemble migraine or cluster headaches. Thus, if you are one of those living with chronic pain or headaches, then it is vital to know more about the drugs that are often associated with headaches.
Early studies have shown that abusing painkillers may cause headaches. In addition, almost all painkillers, if abused, may increase pain sensation and cause headaches. Thus, people abusing NSAIDs, acetaminophen, opioids, and other analgesics are more likely to suffer from chronic migraine disorder. The risk is exceptionally high in those using these drugs for 10-15 days a month and for more than three months.
However, new studies suggest that the problem is worse than imagined. Even some of the new drugs used to treat inflammation, chronic pain, and autoimmune disorders may cause headaches. For example, drugs like monoclonal antibodies, immunomodulators, antivirals, and pulmonary artery dilators are commonly associated with chronic headaches. This new study was presented at the annual meeting of the American Headache Society.
For the study, investigators analyzed the US FDA data, which shows the possible side effects of various drugs. It also records the side effects reported by clinicians. Thus, researchers say they were quite surprised to see how commonly immunosuppressants and immunomodulators were associated with headaches.
These drugs are often needed to treat severe health conditions, and many people need to use them regularly. Quite often, substituting these drugs is not an option. Moreover, it is worth understanding that the study only analyzed the reports of side effects. However, many cases go unreported. Thus, the real risk of headaches from these drugs might be much higher.
Interestingly enough, researchers also found that some drugs belonging to this class of drugs were much less likely to cause headaches. This has perplexed researchers, as it becomes really difficult to understand why some drugs in the same class cause headaches and others do not. For the study, researchers used US FDA adverse event reporting system data to investigate the reports of headaches caused by medications from 2018 to 2020. It is a pharmacovigilance database where doctors or patients may report adverse effects they experienced from drugs approved for clinical use.
They found that headaches were pretty common with apremilast, with 8,672 reports. Other drugs affecting the immune system and commonly associated with headaches were adalimumab (5,357), tofacitinib (4,276), fingolimod (4,123), and etanercept (4,111). These drugs are often used to treat conditions like psoriasis, inflammatory bowel disease, and multiple sclerosis. But unfortunately, all these are difficult-to-treat conditions with fewer treatment options. Thus, quite often, changing the drug therapy is not an option.
Other drugs that the study found to be commonly associated with headaches were drugs used to treat hepatitis C, pulmonary hypertension, arthritis, and asthma. Of course, it is relatively simple to understand why some drugs, like those for pulmonary hypertension, cause headaches. Those drugs are also likely to affect other blood vessels, thus causing headaches. However, researchers still cannot explain why many other drugs cause headaches.
Investigators say that they understand that this is not the best way to understand the adverse effects of drugs. After all, many of these adverse effects were reported by individuals. Moreover, these are not findings of clinical studies, and such kinds of data sets do not provide highly reliable information. Nonetheless, researchers say that these findings are suggestive, and these issues require further scientific investigation.
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, followed by 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, when overused, can increase pain sensitivity 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. Medicines for pulmonary hypertension also act on other blood vessels, and that effect can trigger headaches. For many others, including drugs in the same class where one causes headaches and another rarely does, researchers still cannot explain why. That puzzle is one reason these findings need further 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 alternatives, and 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 medication, 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, not results from clinical studies, so it cannot give highly reliable numbers. It 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
