Metronidazole Barbiturates

Drugs that may affect barbiturates include alcohol, charcoal, chloramphenicol, MAO inhibitors, rifampin, and valproic acid. Drugs that may be affected by barbiturates include acetaminophen, anticoagulants, beta blockers, carbamazepine, chloramphenicol, clonazepam, oral contraceptives, corticosteroids, digitoxin, doxorubicin, doxycycline, felodipine, fenoprofen, griseofulvin, hydantoins, methoxyflurane, metronidazole, narcotics, phenmetrazine, phenylbutazone, quinidine, theophylline, and verapamil. 

Drugs that may affect metronidazole include barbiturates and cimetidine. Drugs that may be affected by metronidazole include anticoagulants, disulfiram, ethanol, hydantoins, and lithium. 

Lopinavir/Ritonavir (Kaletra) [Anrirelroviral/Protease Inhibitor] Uses HIV Infxn Action Protease inhibitor Dose Adults. Tx naive 2 tab PO daily or 1 tab PO bid Tx experiencedpt 1 tab PO bid (T dose if w/ amprenavir, efavirenz, fosamprenavir, nelfinavir, nevirapine) Peds. 7-15 kg 12/3 mg/kg PO bid 15-40 kg 10/2.5 mg/kg PO bid >40 kg Adult dose w/ food Caution [C, /-] Numerous interactions Contra w/drugs dependent on CYP3A/CYP2D6 (Table VI-8) Disp Tab, soln SE Avoid disulfiram (soln has EtOH), metronidazole GI upset, asthenia, T cholesterol/triglycerides, pancreatitis protease metabolic synd Interactions T Effects Wl clarithromycin, erythromycin T effects OF amiodarone, amprenavir, azole andfungals, bepridil, cisapride, cyclosporine, CCBs, ergot alkaloids, flecainide, flurazepam, HMG-CoA reductase inhibitors, indinavir, lidocaine, meperidine, midazolam, pimozide, propafenone, propoxyphene, quinidine, rifabutin, saquinavir, sildenafil, tacrolimus, terfenadine, triazolam, zolpidem 1 effects Wl barbiturates, carbamazepine, dexamethasone, didanosine, efavirenz, nevirapine, phenytoin, rifabutin, rifampin, St. John s wort 1 effects OF OCPs, warfarin EMS Use andarrhythmics and benzodiazepines... 

Warfarin antagonists include vitamin K, barbiturates, glutethimide. rifampin, and cholestyramine. Warfarin potentiators include phenylbutazone. oxyphenbutazone, anabolic steroids, clofibrate, aspirin, hepatotoxins, disnlfirain, and metronidazole. In patients undergoing anticoagulation therapy with warfann, it has been found that cimetidine (used in therapy of duodenal ulcer) may increase anticoagulant blood levels and consequently prolong the prothrombin time. 

METRONIDAZOLE BARBITURATES 1 levels of these drugs, with risk of therapeutic failure Induction of hepatic metabolism. Unlikely with topical metronidazole 1. Avoid co-administration of telithromycin for up to 2 weeks after stopping phenobarbital... 

Clinically important, potentially hazardous interactions with amiodarone, anabolic steroids, antithyroid agents, barbiturates, bivalirudin, cimetidine, clofibrate, clopidogrel, cyclosporine, delavirdine, dextrothyroxine, disulfiram, fluconazole, glutethimide, imatinib, itraconazole, ketoconazole, metronidazole, miconazole, penicillins, phenylbutazones, piperacillin, quinidine, quinine, rifabutin, rifampin, rifapentine, rofecoxib, salicylates, sulfinpyrazone, sulfonamides, testosterone, thyroid, zileuton... 

Common causes of fixed eruptions are ampicillin, aspirin, barbiturates, dapsone, metronidazole, NSAIDs, oral contraceptives, phenolphthalein, phenytoin, quinine, sulfonamides, and tetracyclines. 

While the etiology of idiopathic pityriasis rosea is unknown, we do know that various medications have been reported to give rise to this disorder. These are barbiturates, beta-blockers, bismuth, captopril, donidine, gold, griseofulvin, isotretinoin, labetalol, meprobamate, metronidazole, penicillin, and tripelennamine. 

C9 Amiodarone, chloramphenicol, cimetidine, isoniazid, metronidazole, SSRIs, zafirlukast Barbiturates, chloramphenicol, doxorubicin, ibuprofen, phenytoin, chlorpromazine, steroids, tolbutamide, (S>warfarin... 

An established and clinically important interaction. Monitor the effects of concurrent use and anticipate the need to increase the metronidazole dosage two to threefold if phenobarbital is given. All of the barbiturates are potent liver enzyme inducers and would therefore be expected to interact similarly. 

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