Dextromethorphan Fluoxetine

Dextromethorphan is known to interact with quini-dine and terbinafine. In both cases, there is a reduction in the metabolism of dextromethorphan by the liver. Terbinafine is a drug used to treat fungal infections. Quinidine is used for the treatment of malarial infections and heart rhythm problems. There has been a case report of a drug interaction between the use of fluoxetine (Prozac) and dextromethorphan. Fluoxetine is an antidepressant in the class of drugs called serotonin reuptake inhibitors. 

D6 2.5 18.8 codeine, desipramine, dextromethorphan, fluoxetine, haloperidol, imipramine quinidine, ajmaline... 

B. lit addition, severe rigidity and hyperthermia may occur when patients receiving MAO inhibitors use therapeutic doses of meperidine (Demeroi), dextromethorphan, fluoxetine (Prozac), paroxetine (Paxii), sertraiine (Zoloft), ven-lafaxine (Effexor), or tryptophan the mechanism is unknown but may be related to inhibition of serotonin metabolism in the CNS, resulting in serotonin syndrome (see p 22). 

Codeine, dextromethorphan, haloperidol, thioridazine, perphenazine, nortriptyline, desipramine, fluoxetine, norfluoxetine, TCAs (hydroxylation), beta-blockers such as timolol and metoprolol, type 1C antiarrhythmics encainide, flecainide TCAs (desmethylation), triazolam, alprazolam, midazolam, carbamazepine, terfenadine, quinidine, lidocaine, erythromycin, cyclosporin... 

Dextromethorphan (Mediquell, Benylin DM, PediaCare 1, Delsym, Others) [OTC] [Antitussive] Uses Control nonproductive cough Action Suppresses medullary cough center Dose Adults. 10-30 mg PO q4h PRN (max 120 mg/24 h) Peds. 2-6 y 2.5-7.5 mg q4-8h (max 30 mg/24 h) 7-12 y 5-10 mg q4-8h (max 60 mg/24/h) Caution [C, /-] Not for persistent or chronic cough Contra < 2 y. Disp Caps, lozenges, syrup, Liq SE GI disturbances Interactions T Effects W/ amiodarone, fluoxetine, quinidine, terbinafme T risk of serotonin synd Wf sibutramine, MAOIs T CNS depression Wf antihistamines, antidepressants, sedative, opioids, EtOH EMS Will not affect cough caused by asthma,... 

D6 Bufuralol, bupranolol, clomipramine, clozapine, codeine, debrisoquin, dextromethorphan, encainide, flecainide, fluoxetine, guanoxan, haloperidol, hydrocodone, 4-methoxy-amphetamine, metoprolol, mexile-tine, oxycodone, paroxetine, phenformin, propafenone, propoxyphene, risperidone, selegiline (deprenyl), sparteine, thioridazine, timolol, tricyclic antidepressants Unknown Quinidine, paroxetine... 

D6 Debrisoquine, sparteine, bufuralol, propanolol, thioridazine, quinidine, phenytoin, fluoxetine NNK3 Dextromethorphan, [bufuralol (4 -OH)... 

D6 Desipramine, dextromethorphan, atomoxetine Paroxetine, quinidine, fluoxetine (use of PM vs. EM subjects) None identified... 

Timolol Desip ra mine Fluoxetine Fluvoxamine Imipramine Mianserin Nortriptyline Paroxetine Risperidone Thioridazine Zuclopenthixol Perhexiline Propafenone Sparteine Dextromethorphan Phenformin Tramadol... 

Achamallah NS. Visual hallucinations after combining fluoxetine and dextromethorphan. Am J Psychiatry 1992 149(10) 1406. 

In 31 healthy men and women (mean age 28 years) the ability of four SSRIs (fluoxetine, fluvoxamine, paroxetine, and sertraline) to inhibit CYP2D6 activity was assessed in vivo, as judged by the dextromethorphan test (63). All were extensive metabolizers of dextromethorphan. After 8 days treatment at therapeutic doses, four of eight paroxetine-treated and five of eight fluoxetine-treated subjects had become poor metabolizers, presumably because of the inhibitory effect of the two SSRIs... 

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 amitriptyline, amoxapine, clomipramine, desipramine, desvenlafaxine, dextromethorphan, doxepin, fluoxetine, fluvoxamine, imipramine, meperidine, nortriptyline, paroxetine, protriptyline, sertraline, sibutramine, trazodone, tricyclic antidepressants, trimipramine, venlafaxine... 

Clinically important, potentially hazardous interactions with amitriptyline, amoxapine, amphetamines, bupropion, citalopram, clomipramine, cyproheptadine, desipramine, dextroamphetamine, dextromethorphan, diethylpropion, dopamine, doxepin, entacapone, ephedra, ephedrine, epinephrine, fluoxetine, fluvoxamine, ginseng, imipramine, levodopa, mazindol, meperidine, methamphetamine, nefazodone, nortriptyline, paroxetine, phendimetrazine, phentermine, phenylephrine, pizotifen, propoxyphene, protriptyline, pseudoephedrine, rizatriptan, sertraline, sibutramine, sumatriptan, sympathomimetics, tramadol, tricyclic antidepressants, trimipramine, tryptophan, venlafaxine, zolmitriptan... 

Clinically important, potentially hazardous interactions with desvenlafaxine, dextromethorphan, dihydroergotamine, ephedra, ergot, fluoxetine, fluvoxamine, isocarboxazid, linezolid, lithium, MAO inhibitors, meperidine, methysergide, naratriptan, nefazodone, paroxetine, phenelzine, rizatriptan, sertraline, sumatriptan, tranylcypromine, tryptophan, venlafaxine, verapamil, zolmitriptan, zuclopenthixol... 

CYP2D6 5 25 S-metoprolol Carvedilol Dextromethorphan Nortriptyline Propanolol Odansetron Chlorpromazine Codeine Flecainide Fluoxetine Haloperidol Amiodarone Fluoxetine Methadone Celecoxib Doxorubicin ... 

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... 

Extracted acetazolamide, amitriptyline, chlordiazepoxide, chlorpromazine, desipramine, dextromethorphan, diphenhydramine, doxepin, encainide, fentanyl, flecainide, fluoxetine, flurazepam, haloperidol, hydroxyethylflurazepam, ibuprofen, imipramine, lidocaine, ma-protiline, methadone, methaqualone, mexiletine, norchlorimipramine, nordoxepin, norfluoxetine, nordiazepam, nortriptyline, norverapamil, pentazocine, promazine, propafenone, propoxyphene, propranolol, protriptyline, quinidine, temazepam, trazodone, tri-mipramine, verapamil... 

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