title: Narcotic analgesics in headache.
mesh_terms: D000701:Analgesics, Opioid / Q000009:adverse effects*; D006261:Headache / Q000188:drug therapy*; D006801:Humans; D013375:Substance Withdrawal Syndrome / Q000209:etiology; D019966:Substance-Related Disorders / Q000209:etiology
chemical_list: D000701:Analgesics, Opioid