Tolbutamide Cimetidine

Hepatic enzyme inducers may enhance the metabolism of sulphonylureas that are metabolised in the liver (tolbutamide). Cimetidine, an inhibitor of drug metabolising enzymes, increases metformin plasma concentration and effect. 

Drugs that may affect valproic acid include carbamazepine, charcoal, chlorpromazine, cholestyramine, cimetidine, erythromycin, ethosuximide, felbamate, lamotrigine, phenytoin, rifampin, and salicylates. Drugs that may be affected by valproic acid include carbamazepine, clonazepam, diazepam, ethosuximide, lamotrigine, phenobarbital, phenytoin, tolbutamide, tricyclic antidepressants, warfarin, and zidovudine. 

Clinically important, potentially hazardous interactions with aluminum, aminophylline, aspirin, chlorambucil, cimetidine, clarithromycin, cyclophosphamide, cyclosporine, dicumarol, diuretics, docetaxel, estrogens, grapefruit juice, indomethacin, influenza vaccines, itraconazole, ketoconazole, lansoprazole, live vaccines, methotrexate, montelukast, omeprazole, oral contraceptives, pancuronium, phenobarbital, phenytoin, ranitidine, rifampicin, rifampin, timolol, tolbutamide, vitamin A... 

Cimetidine, fluconazole, fluvastatin, isoniazid, lovastatin, pravastatin, simvastatin, sulfaphenazole, tienilic acid, tolbutamide, warfarin... 

Also analyzed acebutolol, acepromazine, acetaminophen, acetazolamide, acetophenazine, albuterol, amitriptyline, amobarbital, amoxapine, antipsrrine, atenolol, atropine, azata-dine, baclofen, benzocaine, bromocriptine, brompheniramine, brotizolam, bupivacaine, buspirone, butabarbital, butalbital, caffeine, carbamazepine, cetirizine, chlorqyclizine, chlordiazepoxide, chlormezanone, chloroquine, chlorpheniramine, chlorpromazine, chlorpropamide, chlorprothixene, chlorthalidone, chlorzoxazone, cimetidine, cisapride, clomipramine, clonazepam, clonidine, clozapine, cocaine, codeine, colchicine, qyclizine, (yclo-benzaprine, dantrolene, desipramine, diazepam, diclofenac, diflunisal, diltiazem, diphenhydramine, diphenidol, dipheno late, dipyridamole, disopyramide, dobutamine, doxapram, doxepin, droperidol, encainide, ethidium bromide, ethopropazine, fenoprofen, fentanyl, flavoxate, fluoxetine, fluphenazine, flurazepam, flurbiprofen, fluvoxamine, fii-rosemide, glutethimide, glyburide, guaifenesin, haloperidol, homatropine, hydralazine, hydrochlorothiazide, hydrocodone, hydromorphone, hydro g chloroquine, hydroxyzine, ibuprofen, imipramine, indomethacin, ketoconazole, ketoprofen, ketorolac, labetalol, le-vorphanol, lidocaine, loratadine, lorazepam, lovastatin, loxapine, mazindol, mefenamic acid, meperidine, mephenytoin, mepivacaine, mesoridazine, metaproterenol, methadone, methdilazine, methocarbamol, methotrexate, methotrimeprazine, methoxamine, methyl-dopa, methylphenidate, metoclopramide, metolazone, metoprolol, metronidazole, midazolam, moclobemide, morphine, nadolol, nalbuphine, naloxone, naphazoline, naproxen, nifedipine, nizatidine, norepinephrine, nortriptyline, oxazepam, oxycodone, oxymetazo-line, paroxetine, pemoline, pentazocine, pentobarbital, pentoxifylline, perphenazine, pheniramine, phenobarbital, phenol, phenolphthalein, phentolamine, phenylbutazone, phenyltoloxamine, phenytoin, pimozide, pindolol, piroxicam, pramoxine, prazepam, prazosin, probenecid, procainamide, procaine, prochlorperazine, procyclidine, promazine, promethazine, propafenone, propantheline, propiomazine, propofol, propranolol, protriptyline, quazepam, quinidine, quinine, racemethorphan, ranitidine, remoxipride, risperidone, salicylic acid, scopolamine, secobarbital, sertraline, sotalol, spironolactone, sulfinpyrazone, sulindac, temazepam, terbutaline, terfenadine, tetracaine, theophylline, thiethyl-perazine, thiopental, thioridazine, thiothixene, timolol, tocainide, tolbutamide, tolmetin, trazodone, triamterene, triazolam, trifluoperazine, triflupromazine, trimeprazine, trimethoprim, trimipramine, verapamil, warfarin, xylometazoline, yohimbine, zopiclone... 

Drugs such as cimetidine, feibamate, fluconazole, fluoxetine, fluvoxamine, omeprazole, teniposide, tolbutamide, and troglitazone that inhibit the cytochrome P450 enzyme CYP2C19 thereby inhibit the metabolism of topiramate and can increase its serum levels. 

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

The pharmacokinetics of tolbutamide 250 mg daily for 4 days were not significantly changed in 7 healthy subjects when cimetidine 800 mg daily was added for a further 4 days. Other studies also found no pharmacokinetic interaction between tolbutamide and cimetidine, or between tolbutamide and ranitidine, and the hypoglycaemic activity of tolbutamide remained unaltered by cimetidine. ... 

In contrast, in another study in healthy subjects, the AUC of tolbutamide was found to be slightly increased by 20% and the elimination half-life decreased by 17% by cimetidine 1.2 g daily, but plasma glucose levels were not significantly changed. Ranitidine 300 mg had no effect. A later study found effectively the same results. ... 

Shah GF, Ghandi TP, Patel PR, Patel MR, Gilbert RN, Shridhsu- PA Tolbutamide and chlorpropamide kinetics in the presence of cimetidine in human volunteers. Indan Drugs (1985) 22,455-8. 

Stocldey C, Keal J, Rolan P, Bochner F, Scmogyi A. Lack of inhibition of tolbutamide hy-droxylation by cimetidine in man EurJ Clin Pharmacol (198 31,235-7. 

Adebayo GI, Coker HAB. Lack of efficacy of cimetidine and ranitidine as inhibitors of tolbutamide metabolism. EurJ Clin Pharmacol (1988) 34,653-6. 

Cate EW, Rogers JF, Powell JR. Inhibition of tolbutamide elimination by cimetidine but not ranitidine. J Clin Pharmacol (198Q 26,372-7. 

No adverse interactions appear to occur with clopidogrel and alu-minium/magnesium hydroxide, atenolol, cimetidine, digoxin, food, insulin, nifedipine, oestrogens, phenobarbital, phenytoin or tolbutamide. 

---