Phenytoin with meperidine

Phenytoin interacts widi many different drugp. For example isoniazid, chloramphenicol, sulfonamides, benzodiazepines, succinimides, and cimetidine all increase phenytoin blood levels. The barbiturates, rifampin, theophylline, and warfarin decrease phenytoin blood levels. When administering the hydantoins with meperidine, die analgesic effect of meperidine is decreased. 

Clinically important, potentially hazardous interactions with alprazolam, amphetamines, astemizole, clarithromycin, clozapine, desipramine, dexibuprofen, dextroamphetamine, diethylpropion, droperidol, duloxetine, erythromycin, haloperidol, imipramine, isocarboxazid, linezolid, lithium, MAO inhibitors, mazindol, meperidine, methamphetamine, midazolam, moclobemide, nortriptyline, phendimetrazine, phenelzine, phentermine, phenylpropanolamine, phenytoin, pimozide, pseudoephedrine, selegiline, serotonin agonists, sibutramine, St John s wort, sumatriptan, sympathomimetics, tramadol, tranylcypromine, trazodone, tricyclic antidepressants, troleandomycin, tryptophan, zolmitriptan... 

Clinically important, potentially hazardous interactions with alfentanil, alfuzosin, alprazolam, amiodarone, amprenavir, aprepitant, astemizole, atazanavir, bepridil, buprenorphine, bupropion, carbamazepine, chlordiazepoxide, ciclesonide, clozapine, conivaptan, cyclosporine, cyproterone, dasatinib, diazepam, dihydroergotamine, ergot alkaloids, estazolam, eszopidone, etravirine, ezetimibe, fentanyl, fesoterodine, flecainide, flurazepam, fluticasone, halazepam, ivabradine, ixabepilone, ketoconazole, lapatinib, levothyroxine, meperidine, meptazinol, methysergide, midazolam, nifedipine, nilotinib, oral contraceptives, phenytoin, pimozide, piroxicam, propafenone, propoxyphene, quazepam, quinidine, ranolazine, rifabutin, rifampin, rifapentine, rimonabant, rivaroxaban, saquinavir, sildenafil, silodosin, simvastatin, solifenacin, St John s wort, tadalafil, temsirolimus, trabectedin, triazolam, vardenafil, voriconazole, zolpidem... 

Chlorpromazine increases the respiratory-depressant effects of meperidine, as do tricyclic antidepressants this is not true of diazepam. Concurrent administration of drugs such as promethazine or chlorpromazine also may greatly enhance meperidine-induced sedation without slowing clearance of the drug. Treatment with phenobar-bital or phenytoin increases systemic clearance and decreases oral bioavailability of meperidine this is associated with an elevation of the concentration of normeperidine in plasma. As with morphine, concomitant administration of an amphetamine has been reported to enhance the analgesic effects of meperidine and its congeners while counteracting sedation. 

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