RESUMEN
UNLABELLED: The aim of this study was to examine the association and changes over time between headaches with or without somatic pain and the self-reported use of pain medication. The study further examined whether the law amendment in 2003 in Norway releasing the sale of nonprescription drugs to shops has changed these relationships. The study is on the basis of repeated self-report cross-sectional studies from 1998 to 2012 in Norway. A total of 27,247 adults were included. As expected, there was a strong association between headache, especially headache with comorbid somatic pain and consumption of prescription versus nonprescription analgesics, although the overall consumption decreased slightly after 2003. We conclude that the strong association between especially headache, whether complicated by somatic pain or not, and the consumption of prescription-free analgesics did not seem to be negatively affected by the prescription regulatory changes. The very high use of nonprescription medication among headache patients suggests the need for continued observation and information regarding the risk of medication-overuse headache. PERSPECTIVE: In Norway, headache was strongly associated with use of over-the-counter analgesics, for other somatic pain prescription analgesics were equally common. Between 1998 and 2012 headache and related analgesic consumption was reduced and other somatic pain increased. Making over-the-counter analgesics available outside pharmacies in 2003 did not increase the self-reported intake.