Tramadol Ondansetron

Ondansetron, tramadol, and metoclopramide were less effective than lidocaine in preventing pain on injection (29-31). Ondansetron and tramadol have been compared in patients being given propofol in a randomized, doubleblind study in 100 patients (32). Tramadol 50 mg... 

Serotonin syndrome SSRIs, second generation antidepressants, MAOIs, linezolid, tramadol, meperidine, fentanyl, ondansetron, sumatriptan, MDMA, LSD, St. John s wort, ginseng Hypertension, hyperreflexia, tremor, clonus, hyperthermia, hyperactive bowel sounds, diarrhea, mydriasis, agitation, coma onset within hours Sedation (benzodiazepines), paralysis, intubation and ventilation consider 5-HT2 block with cyproheptadine or chlorpromazine... 

Memis D, Turan A, Karamanlioglu B, Kaya G, Pamukcu Z. The prevention of propofol injection pain by tramadol or ondansetron. Eur J Anaesthesiol 2002 19(1) 47-51. 

De Witte JL, Schoenmaekers B, Sessler DI, Deloof T. The analgesic efficacy of tramadol is impaired by concurrent administration of ondansetron. Anesth Analg 2001 92(5) 1319-21. 

Arcioni R, della Rocca M, Romano S, Romano R, Pietropaoli P, Gasparetto A. Ondansetron inhibits the analgesic effects of tramadol a possible 5-HT(3) spinal receptor involvement in acute pain in humans. Anesth Analg 2002 94(6) 1553-7. 

Metoprolol Midazolam Naproxen Nifedipine Omeprazole Ondansetron Orphenadrine Phenytoin Piroxicam Progesterone Propafenone Propranolol Quinidine Rifampin Sibutramine Sildenafil Simvastatin Tacrine Tamoxifen Terfenadine Testosterone Theophylline Timolol Tolbutamide Tramadol Triazolam Verapamil Warfarin (R) Warfarin (S) Zolmitriptan Zolpidem... 

Patients who were given a single 4-mg dose of ondansetron one minute before induction of anaesthesia required 26 to 35% more tramadol by patient controlled analgesia (PCA) from 1 to 4 hours postoperatively than those who received placebo. Similarly, a 1-mg/hour ondansetron infusion increased the dose of postoperative tramadol used during PCA by two- to threefold in 30 patients, when compared with 29 patients who received placebo. Moreover, in this study the group receiving ondansetron actually experienced more vomiting, probably because they used more tramadol, which caused an emetic effect not well controlled by the ondansetron. ... 

On theoretical grounds ondansetron (a S-HTj-receptor antagonist) might be expected to decrease the effects of drugs that reduce pain transmission because serotonin (5-HT) is thought to affect pain responses via presynap-tic 5-HTj receptors in the spinal dorsal horn. This has been demonstrated for tramadol, ch is not a pure opioid and also acts by enhancing the effects of serotonin and noradrenaline (norepinephrine). However, ondansetron had no effect on alfentanil or morphine analgesia in healthy subjects. 

The interaction between ondansetron and tramadol appears to be established and of clinical importance. Ondansetron may double the dose requirement of tramadol, and so result in increased emetic effects, consequently ondansetron does not appear to be the best antiemetic to use with tramadol. Although not tested, other 5-HT3-receptor antagonists would be expected to interact similarly. Ondansetron appears to have no effect on alfentanil or morphine. 

Ondansetron may be associated with an increase in patient-controlled administration of tramadol. 

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