Itching after intrathecal morphine. Incidence and treatment.
This study was designed to determine whether low doses of intrathecal morphine still result in itching and it evaluates the outcome of a standardized treatment using promethazine and - for intractable itch - naloxone. Patients (n = 143) scheduled for total hip surgery were allocated to four groups (in a double blind manner) with bupivacaine 20 mg in 4 mL but different doses of intrathecal morphine: Group I, 0.025 mg, Group II, 0.05 mg, Group III, 0.1 mg and Group IV, 0.2 mg. The presence or absence of itching was noted every three hours for a 24-h period. When required, standardized treatment was provided. The incidence of itching was: Group I: 14. 3%; Group II: 21.6%; Group III: 48.6%; and, Group IV: 61.7%. Itch was treated by administering promethazine intramuscularly in 2.9% (Group I); 8.1% (Group II); 10.8% (Group III), and 8.9% (Group IV), respectively. Only in group IV there was a single patient who needed naloxone to treat itching. The incidence and severity of itching is a dose-related side-effect in the dose range of 0.025-0.2 mg of intrathecal morphine. Itching still occurs after the low doses of intrathecal morphine, but symptoms vanish after promethazine 25 mg intramuscularly.
Slappendel
R
R
Sint Maartenskliniek, PO Box 9011, 6500 GM Nijmegen, The Netherlands.
Weber
E W
EW
Benraad
B
B
van Limbeek
J
J
Dirksen
R
R
D000368:Aged; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000009:adverse effects*; D000982:Antipruritics / Q000627:therapeutic use; D019644:Arthroplasty, Replacement, Hip; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D006801:Humans; D007278:Injections, Spinal; D008875:Middle Aged; D009020:Morphine / Q000008:administration & dosage / Q000009:adverse effects*; D009270:Naloxone / Q000627:therapeutic use; D009292:Narcotic Antagonists / Q000627:therapeutic use; D010149:Postoperative Pain / Q000188:drug therapy*; D011398:Promethazine / Q000627:therapeutic use; D011537:Pruritus / Q000139:chemically induced* / Q000628:therapy
D000701:Analgesics, Opioid; D000982:Antipruritics; D009292:Narcotic Antagonists; D009270:Naloxone; D009020:Morphine; D011398:Promethazine