Thioridazine Propranolol

A 28-year-old man received interferon alfa (5 MU/day for 28 days) for chronic hepatitis B. At the end of treatment he developed a slight parkinsonian gait, and 8 days later had a fever with vomiting, insomnia, restlessness, and raised serum creatine kinase activity (4946 IU/1). He had severe akathisia with psychomotor excitement and parkinsonism. Despite treatment with clonazepam, thioridazine, propranolol, trihexyphenidyl, and bromocriptine, his condition progressively worsened. He was finally given intravenous levodopa for 8 days and recovered dramatically within the next few days. 

Thioridazine Drugs that prolong the QT interval - CYP2D6 inhibitors (eg, fluoxetine, fluvoxamine, paroxetine, pindolol, propranolol)... 

Silver JM, Yudofsky SC, Kogan M, et al Elevation of thioridazine plasma levels by propranolol. Am J Psychiatry 143 1290-1292, 1986... 

Cyt 2D6 metabolizes haloperidol, risperidone, thioridazine, sertindole, olanzapine and clozapine common substrates - fluoxetine, paroxetine, sertraline, venlafaxine, amitriptyline, clomipramine, desipramine, imipramine, nortriptyline, propranolol, metoprolol, timolol, codeine, encainide, flecanide. Common inhibitors - paroxetine, sertraline, fluoxetine. 

Counseling and other psychosocial services play a role in withdrawal therapy.30 Supportive drugs for withdrawal therapy include diphenoxylate with atropine, promethazine, propranolol, thioridazine, benzodiazepines, and chlormethiazole—the use of which all require care and caution. Gerada et al.31 have discussed problems associated with the management of pregnant patients with opioid dependence. 

The combination of propranolol or pindolol with thioridazine should be avoided if possible (32). 

Greendyke RM, Kanter DR. Plasma propranolol levels and their effect on plasma thioridazine and haloperidol concentrations. J Clin Psychopharmacol 1987 7(3) 178-82. 

Fluvoxamine, propranolol, and pindolol also inhibit thioridazine metabolism and can raise thioridazine to dangerous levels... 

CYP2D6 Antidepressants amitriptyline, clomipramine, imipramine, desipramine, nortriptyline, trimipramine, N-desmethyl-clomipramine, fluoxetine, norfluoxetine, paroxetine, venlafaxine, sertraline Neuroleptics chlorpromazine, thioridazine, perphenazine, haloperidol, reduced haloperidol, risperidone, clozapine, sertindole Others codeine, opiate, propranolol, dextromethorphan 4 no activity 25% in Caucasians 0%-10% in others 5 no activity 2%-10% in all groups 10 reduced activity 47%-70% in Asians <5% in others 17 reduced activity 25%-40% in blacks 0% in others 2XN increased activity 19%-29% in Arabs and Ethiopians <5% in others... 

Clinically important, potentially hazardous interactions with albuterol, alpha-blockers, amitriptyline, amoxapine, atenolol, beta-blockers, carteolol, chlorpromazine, clomipramine, cocaine, desipramine, doxepin, ephedra, ergotamine, furazolidone, halothane, imipramine, insulin detemir, MAO inhibitors, metoprolol, nadolol, nortriptyline, oxprenolol, penbutolol, phenelzine, phenoxybenzamine, phenylephrine, pindolol, prazosin, propranolol, protriptyline, sympathomimetics, terbutaline, thioridazine, timolol, tranylcypromine, tricyclic antidepressants, trimipramine, vasopressors... 

Noninterfering N-acetylprocainamide, amitriptyline, caffeine, chlordiazepoxide, chlor-promazine, diazepam, flurazepam, lorazepam, oxazepam, prazepam, procainamide, propranolol, thioridazine... 

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 chlorpromazine, desipramine, desmethyldoxepin, disopyramide, doxepin, imipramine, maprotiline, nortriptyline, procainamide, propoxyphene, propranolol, thioridazine, trimipramine... 

Also analyzed acebutolol, acetaminophen, alprazolam, amphetamine, atenolol, betaxolol, brotizolam, caffeine, camazepam, captopril, chloroquine, clobazam, clomipramine, cloth-iapine, clotiazepam, cloxazolam, cocaine, codeine, diclofenac, dihydralazine, dihydrocodeine, dihydroergotamine, diphenhydramine, domperidone, doxepin, droperidol, ergota-mine, ethyl loflazepate, fenethylline, fluoxetine, flupentixol, flurazepam, furosemide, gliclazide, hydrochlorothiazide, hydroxyzine, ibuprofen, imipramine, ketazolam, loprazo-1am, lorazepam, lormetazepam, maprotUine, medazepam, mepyramine, methadone, methaqualone, methyldopa, methylphenidate, metoclopramide, metoprolol, mexiletine, mianserin, midazolam, minoxidil, morphine, nadolol, nitrazepam, oxprenolol, papaverine, pentazocine, phenprocoumon, phenylbutazone, pipamperone, piritramide, practolol, pra-zepam, prazosin, promazine, promethazine, propoxyphene, propranolol, prothipendyl, quinine, sotalol, sulpride, thioridazine, trazodone, triazolam, trimipramine, tripelennamine, lyramine, verapeunil, yohimbine... 

Extracted amoxapine, brompheniramine, chlorpheniramine, chlorpromazine, clomipramine, c5q)roheptadine, dsipramine, diphenhydramine, dothiepin, doxepin, fluoxetine, hal-operidol, imipramine, loxapine, maprotihne, meperidine, mesoridazine, methadone, metoclopramide, mianserin, moclobemide, nomifensine, nordoxepin, norfluoxetine, norpropoxyphene, northiaden, nortriptyline, pentobarbital, pheniramine, propojgrphene, propranolol, protriptyline, quinidine, quinine, sulforidazine, thioridazine, thiothixene, tranylcypromine, trazodone, trihe q)henidyl, triprolidine Nonintetfering dextromethorphan, norphetidine, pheno benzamine, prochlorperazine, trifluoperazine... 

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