Amitriptyline-fluphenazine

A 41-year-old man developed acute abdominal pain with profuse diarrhea and fever (39°C) while receiving intramuscular fluphenazine decanoate 125 mg once every 3 weeks. During the previous 3 months he had also taken oral alimemazine 50 mg/day, levomeproma-zine 50 mg/day, and amitriptyline 100 mg/day. Colonoscopy showed necrotic ulcers in the mucosa of the sigmoid and descending colon. After three weeks of parenteral nutrition, there was a marked reduction in the colonic lesions and he recovered. Levomepromazine 50 mg/day and fluphenazine decanoate 100 mg/day were reintroduced. Two days later he complained again of abdominal pain, and tomodensi-tometry confirmed distension. 

Drugs that are known to be substrates of P-gp include antihistamines (e.g. terfenadine), digoxin, ciclosporin, hydrocortisone and other steroids and drugs used in chemotherapy (e.g. paclitaxel, vinblastine). Ciclosporin, in addition to being a substrate of P-gp, is also an inhibitor of P-gp. Drugs known to induce P-gp include morphine, dexamethasone, phenobarbital, rifampin and St John s wort. Inhibitors of P-gp include amiodarone, amitriptyline, atorvastatin, chlorpromazine, ciclosporin, erythromycin, fluphenazine, haloperidol, quinidine, ritonavir and verapamil,... 

Clinically important, potentially hazardous interactions with amiodarone, amisulpride, amitriptyline, amoxapine, arsenic, bepridil, bretylium, calcium, chlorpromazine, clomipramine, desipramine, disopyramide, doxepin, erythromycin, fluphenazine, imipramine, iron salts, magnesium, mesoridazine, nortriptyline, pentamidine, perphenazine, phenothiazines, pimozide, procainamide, prochlorperazine, promazine, promethazine, protriptyline, quinidine, sotalol, sucralfate, thioridazine, tricyclic antidepressants, trifluoperazine, trimipramine, zinc salts... 

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... 

Simultaneous amitriptyline, chlorpromazine, clomipramine, dothiepin, doxepin, fluoxetine, fluphenazine, haloperidol, imipramine, maprotiline, mianserin, norclomipramine, nordothiepin, nordoxepin, norfluoxetine, nortriptyline, paroxetine, remoxipride, sertraline, sulpride, thioridazine, trazodone... 

Noninterfering amitriptyline, benztropine methanesulfonate, butaperazine, butriptyline, carphenazine, chlorpromazine, clomipramine, cyclobenzaprine, dextropropoxyphene, dronabinol, ephedrine, ethchlorvynol, fluoxetine, fluphenazine, imipramine, meprobamate, methadone, methamphetamine, nicotine, norfluoxetine, nortriptyline, PCP, pheno-thiazine, pseudoephedrine... 

Also analyzed acebutolol, acepromazine, acetaminophen, acetazolamide, acetophenazine, albuterol, alprazolam, amitriptyline, amobarbital, amoxapine, antip3rrine, atenolol, atropine, azatadine, baclofen, benzocaine, bromocriptine, brompheniramine, brotizolam, bupivacaine, buspirone, butabarbital, butalbital, caffeine, carbamazepine, cetirizine, chlorcyclizine, chlordiazepoxide, chlormezanone, chloroquine, chlorpheniramine, chlorpromazine, chlorpropamide, chlorprothixene, chlorthalidone, chlorzoxazone, cimeti-dine, cisapride, clomipramine, clonazepam, clonidine, clozapine, coceune, colchicine, ethidium bromide, ethopropazine, fenoprofen, fentanyl, flavoxate, fluoxetine, fluphenazine, flurazepam, flurbiprofen, fluvox-amine, furosemide, glutethimide, glyburide, guaifenesin, haloperidol, homatropine, hydralazine, hydrochlorothiazide, hydrocodone, hydromorphone, hydroxychloroquine, hydroxyzine, ibuprofen, imipramine, indomethacin, ketoconazole, ketoprofen, ketorolac, labetalol, levorphanol, lidocaine, loratadine, lorazepam, lovastatin, loxapine, mazindol. 

Extracted amitriptyline, chlordiazepoxide, chlorpromeizine, desipramine, desmethldiaze-pam, desmethylchlordiazepoxide, desmethyldoxepin, doxepin, fluphenazine, haloperidol, nortriptyline, oxazepam, thiothixene Noninterfering molindone, perphenazine, trifluoperazine Interfering imipramine... 

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