With the simultaneous use of verapamil with:
- enhances AUC (area under the concentration-time curve) of carbamazepine in patients with stable partial epilepsy (risk of side effects such as diplopia, headache, ataxia and dizziness).
- enhances AUC, Css (ground clearance) and Cmax (the maximum concentration of the drug) of cyclosporine.
- enhances AUC and Cmax glibenclamide.
- increases the concentration of sirolimus and tacrolimus.
- significantly increases AUC and Cmax buspirone and midazolam.
- increases the concentration of theophylline (due to lower clearance), ethanol (and lengthens its effect), the concentration of quinidine (the risk of pronounced reduction in blood pressure).
- can increase the concentration of atorvastatin and lovastatin.
- increases significantly AUC and Cmax simvastatin.
- enhances AUC and Cmax almotriptan.
- increases the concentration of cardiac glycosides (requires careful monitoring and reduction of the dose of glycosides).
- enhances AUC and Cmax metoprolol and propranolol in patients with angina pectoris.
- increases the plasma concentration of colchicine (a substrate for CYP3A and p-glycoprotein).
- when taken orally significantly increases AUC and Cmax doxorubicin.
- slightly increases AUC imipramine; does not affect the concentration of the active metabolite, desipramine.
- increases Cmax prazosin and terazosin and AUC terazosin.
- inhibitors CYP3A (including erythromycin, ritonavir and other antiviral HIV drugs), telithromycin increase plasma concentrations of verapamil.
- grapefruit juice increases AUC and Cmax R- and S- isomer of verapamil.
- cimetidine increases the bioavailability of verapamil by almost 40-50% (due to a decrease in hepatic metabolism), so it may be necessary to reduce the dose of the latter.
- rifampicin can significantly reduce bioavailability (up to 92%), and AUC and Cmax verapamil.
- Phenobarbital increases the clearance of verapamil 5 times.
- sulfinpyrazone increases the clearance of verapamil by about 3 times and reduces bioavailability (60%).
- preparations of St. John's wort penetrate lower AUC R- and S- isomer of verapamil and Cmax.
- while simultaneous use with inhalation anesthetics increases the risk of bradycardia, atrioventricular blockade, heart failure.
- a combination with beta-blockers can lead to an increase in the negative inotropic effect, an increased risk of developing atrioventricular conduction disorders, bradycardia (the administration of verapamil and beta-blockers should be performed at intervals of several hours)
- prazosin and other alpha-blockers, as well as other antihypertensive drugs (ATP inhibitors, vasodilators, diuretics, beta-adrenoblockers) increase the hypotensive effect.
- disopyramide and flecainide should not be administered within 48 hours or 24 hours after the use of verapamil (summation of a negative inotropic effect, up to a lethal outcome).
- increases the risk of neurotoxic effect of lithium preparations.
- enhances the action of peripheral muscle relaxants (a change may be required mode of dosing).
- while simultaneous use with acetylsalicylic acid (ASA), there was a slightly greater increase in bleeding time than with ASA alone.
- carbamazepine and lithium increases the risk of neurotoxic effects.