Morphine Gabapentin

Drugs that may affect gabapentin include antacids, cimetidine, hydrocodone, and morphine. Drugs that may be affected by gabapentin include oral contraceptives and hydrocodone. 

Gilron, I., Biederman, J., Jhamandas, K., and Hong, M. (2003). Gabapentin blocks and reverses antinociceptive morphine tolerance in the rat pawpressure and tail-flick tests. Anesthesiology 98,... 

Morphine and hydrocodone may increase plasma AUC (area under the curve) values of gabapentin and thus gabapentin plasma levels overtime... 

Gabapentin has been used to treat morphine-induced myoclonus in a 54-year-old patient with gallbladder cancer (13). Effective pain control was maintained with morphine 300 mg, but after 24 hours the patient developed generalized muscular movements while asleep. Gabapentin 300 mg bd produced complete resolution of symptoms after 12 hours. In another case gabapentin 600 mg/day was used to treat a 1-month history of spontaneous jerking of both wrists after an increase in the dose of morphine to 120 mg/day the myoclonus disappeared over the next 24 hours (8,13). 

Field, M. J. et al., Gabapentin and pregabalin, but not morphine and amitriptyline, block both static and dynamic components of mechanical allodynia induced by streptozocin in the rat, Pain, 80(1-2), 391, 1999. 

Gabapentin has been reported to enhance the analgesic effects of morphine and other opioids. Morphine can increase the bioavailability of gabapentin. 

EckhardtK, Ammon S, Hofmann U, Riebe A, GugelerN, Mikus G. Gabapentin enhances the analgesic effect of morphine in healthy vohmt ers. AnesihAnalg (2000) 91, 185-91. 

Gabapentin Preoperative gabapentin 1200 mg reduced the incidence and severity of morphine-induced pruritus and delayed its time of onset compened with placebo (48% versus 78%) in 86 patients who received preservative-free morphine 0.2 mg intrathecaUy [120 ]. 

Sheen MJ, Ho S-T, Lee C-H, Tsung Y-C, Chang F-L. Preoperative gabapentin prevents intrathecal morphine-induced pruritus after orthopedic surgery. Anesth Analg 2008 106(6) 1868-72. 

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