Influence of pH on the buccal absorption of morphine sulphate and its major metabolite, morphine-3-glucuronide.
Buccal absorption of morphine sulphate and morphine-3-glucuronide at various buffer pH values (4 to 10) over 5 min has been investigated in seven and four normal healthy volunteers, respectively. Increasing pH caused an increase in buccal absorption of both. The maximum mean absorption was 37% at pH 10 for morphine and 19% at pH 8 for morphine-3-glucuronide.
D000278:Administration, Buccal; D002610:Cheek; D006801:Humans; D006863:Hydrogen-Ion Concentration; D009020:Morphine / Q000493:pharmacokinetics*; D009022:Morphine Derivatives / Q000493:pharmacokinetics*; D009061:Mouth Mucosa / Q000378:metabolism*
D009022:Morphine Derivatives; D009020:Morphine; C018108:morphine-3-glucuronide