Methadone Phenobarbital

Methadone Phenobarbital Reduced effect of methadone Increased metabolism... 

Detoxiflcation may be accomplished with phenobarbital (60 mg of phe-nobarbital for 500 mg of glutethimide). If concomitant codeine dependence is present (and this codependence should be strongly suspected), then methadone can be used adjunctively (10 mg of methadone for 120 mg of codeine) (Khajawall et al. 1982). Approximate sedative-hypnotic dosage equivalencies are listed in Table 3-5. 

Phenytoin Similar to phenobarbital may need to increase methadone dose when phenytoin is added to a methadone maintenance drug regimen to avoid withdrawal symptoms. 

St. John s wort, rifamycins, and ritonavir. Drugs that may be affected by efavirenz include phenytoin, phenobarbital, carbamazepine, itraconazole, ketoconazole, methadone, ritonavir, amprenavir, benzodiazepines, clarithromycin, ethinyl estradiol, indinavir, nelfinavir, saquinavir, and warfarin. 

B6 Artemisinin, bupropion, cyclophosphamide, efavirenz, ifosfamide, ketamine, S-mephobarbital, S-mephenytoin (/V-demethylation to nirvanol), methadone, nevirapine, propofol, selegiline, sertraline, ticlopidine Phenobarbital, cyclophosphamide Ticlopidine, clopidogrel... 

D6 Tricyclic antidepressants (TCAs), benztropine, perphenazine, clozapine, haloperidol, codeine/oxycodone, risperidone, class Ic antiarrhythmics, 3 blockers, trazodone, paroxetine, maprotiline, amoxapine, duloxetine, mirtazapine (partly), venlafaxine, bupropion Fluoxetine, paroxetine, duloxetine, hydroxybupropion, methadone, cimetidine, haloperidol, quinidine, ritonavir Phenobarbital, rifampin... 

Efavirenz inhibits the plasma levels of indinavir, saquinavir and amprenavir and increases the concentrations of ritonavir and nelfinavir. It also lowers the plasma levels of methadone, phenytoin, carbamazepine and phenobarbital. Drugs that stimulate the cytochrome P-450 system will increase its clearance and should not be coadministered. 

BARBITURATES ANALGESICS - OPIOIDS 1. Barbiturates t sedative effects of opioids 2.1 efficacy of fentanyl and methadone with phenobarbital and primidone 1. Additive sedative effect. 2. t hepatic metabolism of fentanyl and methadone 1. Monitor respiratory rate and conscious levels 2. Be aware that the dose of fentanyl and methadone may need to t... 

OPIOIDS ANTIEPILEPTICS 1. Barbiturates T sedative effects of opioids 2.1 efficacy of fentanyl and methadone with carbamazepine, phenobarbital, phenytoin or primidone 3. Carbamazepine l tramadol levels 4. Risk of pethidine toxicity 1. Additive sedative effect 2. t hepatic metabolism of fentanyl and methadone, and possibly an effect at the opioid receptor 3. Carbamazepine T metabolism of tramadol 4. Phenytoin induces metabolism of pethidine, which causes T level of a neurotoxic metabolite 1. Monitor respiratoiy rate and conscious levels 2. Be aware that the dose of fentanyl and methadone may need to be t 3. Watch for poor effect of tramadol. Consider using an alternative opioid 4. Co administer with caution the effect may be i by administering pethidine intravenously... 

Alkaline diuresis will favor the excretion of weak acids (anions) such as salicylate or phenobarbital. Indeed, the more the drug is ionized, the more it is trapped in the tubular lumen and consequently is not reabsorbed, hence eliminated in the urine. This mechanism can play a role in the treatment of severe intoxications. The reverse being true for weak bases (cations) such as methadone. Acidification of the urine facilitates the reahsorption of weak acids and will re-... 

Clinically important, potentially hazardous interactions with adefovir, alprazolam, amprenavir, anisindione, anticoagulants, buprenorphine, carbamazepine, dicumarol, dihydroergotamine, ergot, fosamprenavir, indinavir, ixabepilone, lovastatin, methadone, methysergide, midazolam, phenobarbital, phenytoin, quinidine, rifabutin, rifampin, sildenafil, simvastatin, triazolam, warfarin... 

Clinically important, potentially hazardous interactions with abacavir, atorvastatin, bepridil, bupropion, carbamazepine, clarithromycin, cyclosporine, dexamethasone, digoxin, felodipine, fluticasone propionate, fosamprenavir, itraconazole, ketoconazole, lovastatin, methadone, midazolam, nicardipine, nifedipine, phenobarbital, phenytoin, rifabutin, simvastatin, sirolimus, St John s wort, systemic lidocaine, tacrolimus, tenofovir, trazodone, vinblastine, vincristine, voriconazole, warfarin, zidovudine... 

Clinically important, potentially hazardous interactions with amiodarone, astemizole, bepridil, carbamazepine, chloroquine, cisapride, clarithromycin, dihydroergotamine, disopyramide, ergotamine, grapefruit juice, halofantrine, haloperidol, itraconazole, ketoconazole, methadone, moxifloxacin, phenobarbital, phenytoin, pimozide, procainamide, quinidine, rifampicin, ritonavir, sotalol, St John s wort, telithromycin, terfenadine, voriconazole... 

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... 

Ehctracted amphetamine, benzoylecgonine, caffeine, codeine, cotinine, desipramine, diazepam, diphenhydramine, ephedrine, hydrocodone, hydromorphone, lidocaine, methadone, metheimphetamine, morphine, nordiazepam, nortriptyline, oxazepam, pentazocine, phen-metrazine, phenobarbital, phentermine, phenylpropanolamine, secobarbital Interfering flurazepam, imipramine... 

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