Buccal morphine

If disturbances of gastrointestinal function prevent the use of oral sustained-release morphine, the fentanyl transdermal system (fentanyl patch) can be used over long periods. Furthermore, buccal transmucosal fentanyl can be used for short episodes of breakthrough pain (see Alternative Routes of Administration). Administration of strong opioids by nasal insufflation has been shown to be efficacious, and nasal preparations are now available in some countries. Approval of such formulations in the USA is growing. In addition, stimulant drugs such as the amphetamines have been shown to enhance the analgesic actions of the opioids and thus may be very useful adjuncts in the patient with chronic pain. 

Buccal delivery of opioid analgesics and antagonists can improve bioavailability relative to the oral route. Esterification of the 3-pheno-lic hydroxyl group in opioid analgesics such as nalbuphine, naloxone, naltrexone, oxymorphone, butorphanol, and levallorphan improved bioavailability and eliminated the bitter taste. The prodrug of morphine,... 

Although not routinely given by the buccal or sublingual routes, several research studies have shown that absorption of morphine from the mouth gives rise to effective analgesia and that these routes may provide suitable alternatives to parenteral administration. " Clinical studies have suggested that the bioavailability of morphine is 40-50% greater after buccal than intramuscular administration as plasma morphine... 

Ketobemidone is a narcotic analgesic that has been used clinically in Scandinavia and other European countries. The mean bioavailability in humans has been reported to be approximately 35% following oral administration, but this can be substantially improved when administered by the sublingual or buccal route. To date, in vitro work has focussed on the use of the ketobemidone prodrugs (largely esters), and published results suggest that, as with morphine sulfate, buccal mucosa permeation is greatly improved.[4 °l... 

Hoskin, P.J. Hanks, G.W. Aheme, G.W. Chapman, D. Littleton, P. Filshie, J. The bioavailability and pharmacokinetics of morphine after intravenous, oral and buccal administration in healthy volunteers. Br. J. Clin. Pharmacol. 1989, 27, 499-505. 

Al-Sayed-Omar, O. Johnston, A. Turner, P. Influence of PH on the buccal absorption of morphine sulphate and its major metabolite, morphine-3-glucuronide. J. Pharm. Pharmacol. 1987, 39, 934-935. 

There is a similar frequency of adverse effects between buccal and intramuscular morphine, as well as intramuscular and intravenous infusions. 

Experiments with some analgesics showed that the highly lipid-soluble etorphine was absorbed several times more rapidly from the buccal cavity than the less lipid-soluble morphine. Impressive absorption has been... 

Absorption In general, the opioids are absorbed readily from the GI tract absorption through the rectal mucosa is adequate, and a few agents e.g., morphine, hydromorphone) are available in suppositories. The more lipophilic opioids also are absorbed readily through the nasal or buccal... 

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