The effectiveness of oral analgesics (morphine, codeine, acetylsalicylic acid) and the problem of placebo "reactors" and "non-reactors".
D000700:Analgesics; D001241:Aspirin / Q000008:administration & dosage*; D003061:Codeine / Q000008:administration & dosage*; D006801:Humans; D009020:Morphine / Q000008:administration & dosage*; D010919:Placebos
D000700:Analgesics; D010919:Placebos; D009020:Morphine; D001241:Aspirin; D003061:Codeine
ACETYLSALICYLIC ACID/administration; CODEINE/administration; MORPHINE/administration; PLACEBOS