Control of chronic pain in very advanced cancer patients with morphine hydrochloride administered by oral, rectal and sublingual route. Clinical report and preliminary results on morphine pharmacokinetics.

Pharmacological Research Communications 05/1982; 14(4):369-80.
Source: PubMed
1 Follower
3 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: Seven patients undergoing radiological treatment for carcinoma of the uterus were given morphine intramuscularly (0.15 mg X kg-1) and morphine in a starch hydrogel rectally (0.56 mg X kg-1) on two separate occasions. The hydrogel preparation was used to order to improve the contact between the rectal mucosa and thus improve and possibly prolong the absorption of morphine. Plasma concentrations of morphine were followed for 8 h and analysed with a GC/MS technique. It was found that 45-120 min after administration of morphine hydrogel, a mean maximum plasma morphine concentration of 61 ng X ml-1 was obtained. After 8 h, the mean plasma concentration was 10 ng X ml-1. The mean biological availability of morphine hydrogel was 48% (range 31-72%). It is suggested that morphine hydrogel, given rectally, can be clinically useful.
    Acta Anaesthesiologica Scandinavica 11/1984; 28(5):540-3. DOI:10.1111/j.1399-6576.1984.tb02115.x · 2.32 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Methadone is a potent, long acting narcotic analgesic which can be orally administered due to its almost complete bioavailability. There is a growing interest in the rectal route of administration in the case of acute post-operative or chronic malignant pain. Since virtually no data were available on the rectal absorption profile of methadone in man, plasma concentrations of methadone were determined by means of HPLC analysis after a single dose of 10 mg methadone HCl in a cross-over pilot study in five volunteers. The rectal dosage forms included aqueous solutions and fatty suppositories. A comparison was made with an orally administered solution. Compared with oral dosing, the extent of rectal absorption from an aqueous solution was almost 80% up to 8 h after dosing. Although the mean peak concentration and the AUC0-8h was significantly lower (p less than 0.01), no marked difference in tmax was observed: 2.8 and 3.1 h respectively. Rectal absorption conditions of methadone from fatty suppositories (3 ml) were found to be less favourable. The peak plasma concentration was only reached 3-4 h after administration, whereas the relative bioavailability up to 8 h after dosing ranged from 35-58%. This rate-limiting absorption pattern may be due to the critical solubility properties of methadone HCl at physiological pH.
    Pharmaceutisch Weekblad Scientific Edition 01/1985; 6(6):237-40. DOI:10.1007/BF01954551
  • [Show abstract] [Hide abstract]
    ABSTRACT: Rectal absorption of morphine HCl from aqueous vehicles at different pHs in man has been compared with an orally administered solution. Plasma concentrations of morphine were measured by electrochemical HPLC analysis after a single dose of 10 mg morphine HCl, in a cross-over study in 7 volunteers. Rectal absorption of morphine was dependent on pH, which could be explained as being due to pH partitioning. The absorption rate and bioavailability could be greatly improved, as compared to orally administered morphine, by adjusting the pH. It was concluded that a rectal solution adjusted to pH 7 to 8 provided an entirely adequate dosage form.
    European Journal of Clinical Pharmacology 02/1985; 29(1):119-21. DOI:10.1007/BF00547380 · 2.97 Impact Factor
Show more

Similar Publications