Buprenorphine bioavailability

An isolated report describes a marked increase in the effects of dextromoramide, resulting in coma, in a man treated with trole-andomycin. Macrolides including troleandomycin and erythromycin are predicted to increase buprenorphine bioavailability. Similarly, the metabolism of hydromorphone is reduced by troleandomycin in vitro. Some manufacturers have su ested that the metabolism of methadone and oxycodone may be decreased by these macrolides, but there do not appear to be any clinical reports confirming this. 

Lindhardt K, Bagger M, Andreasen KH, Bechgaard E (2001) Intranasal bioavailability of buprenorphine in rabbit correlated to sheep and man. Int J Pharm 217 121-126. 

The bioavailability of the buprenorphine/naloxone tablet appears to be greater than the buprenor-phine-alone formulation, with the former similar to the drug in liquid form. Buprenorphine is approximately 96% plasma protein bound, primarily to a- and [3-globulin. The plasma half-life is... 

Butorphanol, an analog of buprenorphine, showed a nasal bioavailability of 70% and also a much lower Tmax after nasal absorption as compared with the sublingual and buccal routes [115]. Lindhardt et al. [106] compared buprenorphine formulated in 30% PEG-300 in sheep with that of the 5% dextrose formulation mentioned earlier. A unit-dose Pfeiffer device was again used to administer the formulation. It was found that nasal bioavailability in sheep was about 70% when buprenorphine was formulated in PEG-300 and approximately 89% when it was formulated with 5% dextrose. The rate of absorption was reported to be very fast, with a Tmax of 10 min the Cmax was found to be 37 and 48ng/mL for PEG-300 and dextrose, respectively. In sheep, the pharmacokinetics of buprenorphine showed a two-compartment model as compared to a three-compartment model in humans. 

In common with other phenolic opiate analgesics, buprenorphine shows low peroral potency, suggesting a high first-pass metabolism effect indeed, work in rats has shown this to be the case. Intravenous studies have estimated that the extraction ratio of buprenorphine is 85% and that peroral systemic availability is consequently expected to be 15% or less. Although absorption from the mouth is slow and, therefore, not as useful as parenteral administration in the treatment of acute pain, it offers a major bioavailability advantage over the peroral route for this drug. If required, the patient can be given a parenteral dose of buprenorphine to achieve rapid pain relief and... 

Brewster, D. Humphrey, M.J. McLeavy, M.A. The systemic bioavailability of buprenorphine by various routes of administration. J. Pharm. Pharmacol. 1981, 33, 500-506. 

Simojoki K, Ullsunde P, Lintzeris N, Alho H. Bioavailability of buprenorphine from crushed and whole buprenorphine (Subutex) tablets. Eur Addict Res 2010 16(2) 85-90. 

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