Track painkiller days: frequent use can itself cause headaches
Repeated headaches followed by daily painkillers can become a cycle in which the medicine contributes to the headaches. This is called medication-overuse headache. Diagnostic overuse thresholds are at least 15 days a month for ordinary non-opioid painkillers and at least ten days a month for combination painkillers, for more than three months, in someone meeting the other headache criteria. Most patients improve after the overused medicine is withdrawn. These are diagnostic thresholds, not a guarantee that taking medicine just below them is safe.
What it takes
Nothing. Keep a record of the days you take medicine and resist reaching for another dose automatically.
What you may gain
The International Headache Society's International Classification of Headache Disorders, third edition, defines medication-overuse headache as headache on at least 15 days a month in someone with a preexisting headache disorder, together with regular overuse of acute headache medicines for more than three months. For non-opioid painkillers such as acetaminophen, aspirin, and ibuprofen, overuse means use on at least 15 days a month. For combination painkillers, the threshold is at least ten days a month. Combination products contain medicines from two or more classes with pain-relieving effects, or include an adjuvant such as caffeine; acetaminophen with codeine is an example. Days of use count together even if you alternate different non-opioid painkillers. The classification notes that epidemiological evidence from several countries attributes more than half of cases of headache on at least 15 days a month to medication overuse. Most patients improve after withdrawal of the overused medicine, and preventive headache treatments can become more effective.
Context & considerations
Chinese painkiller names containing 咖 often indicate caffeine, placing them in the combination-product category with the ten-day threshold. If you have headaches on more and more days each month, seek a neurology assessment instead of simply adding medicine. The evidence is rated B because the cited classification provides diagnostic criteria, not a controlled trial. The medium benefit rating is a judgment about gaining days without headache; it does not concern mortality.
Research & references
Headache Classification Committee of the International Headache Society (2018). The International Classification of Headache Disorders, 3rd edition. Cephalalgia, 38(1):1–211. https://doi.org/10.1177/0333102417738202; ICHD-3 online, 8.2 Medication-overuse headache, including sections 8.2.3 and 8.2.5. https://ichd-3.org/8-headache-attributed-to-a-substance-or-its-withdrawal/8-2-medication-overuse-headache-moh/