Timolol Flecainide

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... 

Antiarrhythmics encainide, flecainide, mexiletine Beta-blockers alprenolol, metoprolol, propranolol, timolol Opiates codeine, dextromethorphan, ethylmorphine... 

Inhibitors codeine, encainide, flecainide, fluoxetine, haloperidol, hydrocodone, 4-methoxy-amphetamine, metoprolol, mexiletine, oxycodone, paroxetine, propafenone, propoxyphene, risperidone, selegiline (deprenyl), thioridazine, most tricyclic antidepressants, timolol Fluoxetine, haloperidol, paroxetine, quinidine... 

FLECAINIDE BETA-BLOCKERS Risk of bradycardia (occasionally severe), 1 BP and heart failure. Note, a single case report has described bradycardia when timolol eye drops given to a patient on flecainide Additive negative inotropic and chronotropic effects Monitor PR, BP and ECG closely watch for development of heart failure... 

IMATINIB 1. ANTIARRHYTHMICS -flecainide, mexiletine, propafenone 2. ANTIDEPRESSANTS - fluoxetine, paroxetine, TCAs, trazodone, venlafaxine 3. ANTIPSYCHOTICS -clozapine, haloperidol, perphenazine, risperidone, thioridazine 4. BETA-BLOCKERS - metoprolol, propanolol, timolol 5. DONEPEZIL 6. METHAMPHETAMINE Imatinib may cause t plasma concentrations of these drugs, with a risk of toxic effects Inhibition of CYP2D6-mediated metabolism of these drugs Watch for early features of toxicity of these drugs... 

Drugs that are metabolized by the cytochrome P-450 (CYP) isoenzymes CYP2D6, CYP2C9, and CYP2C19 also exhibit genetic polymorphisms. An example of CYP2D6 metabolism is debrisoquine. In about 5-10 /o of Caucasians in North America and Europe and about 1% of Asians, 4-hydroxylation of debrisoquine is reduced, and such individuals are at increased risk for toxicity (orthostatic hypotension). Beta blockers (metoprolol and timolol), antiarrhythmic drugs (encainide and flecainide), tricyclic antidepressants... 

Ajmaline, alprenolol, amiflamine, amphetamine, aprindine, captopril, chlorpheniramine, cinnarizine, citalopram, clomipramine, clozapine, codeine, desipramine, dolasteron, encainide, flecainide, fluoxetine, fluphenazine, haloperidol, hydrocordone, imipramine, loratidine, methoxyphenamine, 3,4-methylenedioxymethamphetamine, metoprolol, mexiletine, (S)- and (i )-mianserin, nifedipine, olanzapine, omeprazole, oxycodone, perhexiline, phenformin, propaphenone, propranolol, remoxipride, ritonavir, saquinavir, selegiline, tamsulosin, timolol, tomoxetine, tramadol, trifluperidol, zolpidem... 

Other case reports and studies describe heart failure, dyspnoea, - sinus arrest, heart block, "" hypotension, " and bradycar-(jj 4,5,8,io,ii,i4-i8 jjj patients taking verapamil with alprenolol, atenolol, metoprolol, " propranolof " or pindolol. In two further cases, bradycardia occurred in patients taking verapamil and using timolol eye drops. Another case has been reported, but this was complicated by the presence of flecainide , (p.844). A number of reports noted that patients experiencing this interaction had reasonable left ventricular function. Heart block and hypotension or cardiogenic shock has also been reported after verapamil was given with atenolol or propranolol in overdose. 

The combined use of flecainide and beta blockers may have additive cardiac depressant effects. An isolated case of bradycardia and fatal AV block has been reported during the use of flecainide with sotalol, and bradycardia has been reported in a patient taking flecainide who was given timolol eye drops. 

Minish T, Herd A. Symptomatic bracfycardia secondary to interacticn between timolol maleate, verapamil, and flecainide acaserepxnL J me/g Mec (2002)22,247-9. 

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