2974
T3D2932
Buprenorphine
Buprenorphine is a derivative of the opioid alkaloid thebaine that is a more potent (25 - 40 times) and longer lasting analgesic than morphine. It appears to act as a partial agonist at mu and kappa opioid receptors and as an antagonist at delta receptors. The lack of delta-agonist activity has been suggested to account for the observation that buprenorphine tolerance may not develop with chronic use. [PubChem]
52485-79-7
40400
C29H41NO4
467.303560
White powder.
1.68e-02 g/L
31% bioavailability (sublingual). Sublingual absorption is also dependent on pH. The length of time the tablet is under the tongue has little effect on absorption. Although buprenorphine is rapidly absorbed from the oral mucosa, the absorption into the systemic is slower. The time to reach peak plasma concentration (Tmax) varies between individuals (range of 40 minutes to 3.5 hours). How buprenorphine is formulated does not affect this pharmacokinetic parameter. It also undergoes extensive first-pass metabolism and as a consequence, has very low oral bioavailability. Coadministration with naloxone does not effect the pharmacokinetics of buprenorphine.
Buprenorphine's analgesic effect is due to partial agonist activity at mu-opioid receptors. Buprenorphine is also a kappa-opioid receptor antagonist. The partial agonist activity means that opioid receptor antagonists (e.g., an antidote such as naloxone) only partially reverse the effects of buprenorphine. The binding to the mu and kappa receptors results in hyperpolarization and reduced neuronal excitability. Furthermore, buprenorphine slowly dissociates from its receptor. This observation would account for the longer duration of action compared to morphine, the unpredictability of its reversal by opioid antagonists, and its low level of manifest physical dependence. Its receptor fixation half life is 40 minutes which is significantly longer than morphine (milliseconds).
Hepatic. Buprenorphine undergoes both N-dealkylation to norbuprenorphine and glucuronidation. The N-dealkylation pathway is mediated by cytochrome P-450 3A4 isozyme. Norbuprenorphine, an active metabolite and has one-fifth of the pharmacologic activity of the parent compound, can further undergo glucuronidation.
Route of Elimination: Buprenorphine, like morphine and other phenolic opioid analgesics, is metabolized by the liver and its clearance is related to hepatic blood flow. It is primarily eliminated via feces (as free forms of buprenorphine and norbuprenorphine) while 10 - 30% of the dose is excreted in urine (as conjugated forms of buprenorphine and norbuprenorphine).
Half Life: IV administration, 0.3 mg = 1.2 - 7.2 hours (mean 2.2 hours);
Sublingual administration = 37 hours.
No indication of carcinogenicity to humans (not listed by IARC).
For the treatment of moderate to severe pain, peri-operative analgesia, and opioid dependence.
Medical problems can include congested lungs, liver disease, tetanus, infection of the heart valves, skin abscesses, anemia and pneumonia. Death can occur from overdose.
Manifestations of acute overdose include pinpoint pupils, sedation, hypotension, respiratory depression and death.
The respiratory and cardiac status of the patient should be monitored carefully. In the event of depression of respiratory or cardiac function, primary attention should be given to the re-establishment of adequate respiratory exchange through provision of a patent airway and institution of assisted or controlled ventilation. Oxygen, intravenous fluids, vasopressors, and other supportive measures should be employed as indicated. In the case of overdose, the primary management should be the re-establishment of adequate ventilation with mechanical assistance of respiration, if required. Naloxone may not be effective in reversing any respiratory depression produced by buprenorphine. High doses of naloxone hydrochloride, 10-35 mg/70 kg may be of limited value in the management of buprenorphine overdose. Doxapram (a respiratory stimulant) also has been used. (L1712)
2009-07-21T20:27:58Z
2014-12-24T20:25:53Z
Buprenorphine
C08007
3216
Buprenorphine
DB00921
true
[H][C@@]12OC3=C(O)C=CC4=C3[C@@]11CCN(CC3CC3)[C@]([H])(C4)[C@]11CC[C@@]2(OC)[C@]([H])(C1)[C@](C)(O)C(C)(C)C
C29H41NO4
InChI=1S/C29H41NO4/c1-25(2,3)26(4,32)20-15-27-10-11-29(20,33-5)24-28(27)12-13-30(16-17-6-7-17)21(27)14-18-8-9-19(31)23(34-24)22(18)28/h8-9,17,20-21,24,31-32H,6-7,10-16H2,1-5H3/t20-,21-,24-,26+,27-,28+,29-/m1/s1
InChIKey=RMRJXGBAOAMLHD-IHFGGWKQSA-N
467.6401
467.303558805
Exogenous
Solid
4.98
HMDB15057
CHEMBL1201894
559124
<p>Kazuhisa Ninomiya, Yasuhiro Fukushima, Mutsuo Okumura, Yuko Hosokawa, “Buprenorphine percutaneous absorption preparation.” U.S. Patent US6090405, issued August, 1992.</p>