Why is this medication prescribed?
Verapil is used to treat high blood pressure and to control angina (chest pain). The immediate-release tablets are also used alone or with other medications to prevent and treat irregular heartbeats. Verapil is in a class of medications called calcium-channel blockers. It works by relaxing the blood vessels so the heart does not have to pump as hard. It also increases the supply of blood and oxygen to the heart and slows electrical activity in the heart to control the heart rate.
High blood pressure is a common condition and when not treated, can cause damage to the brain, heart, blood vessels, kidneys and other parts of the body. Damage to these organs may cause heart disease, a heart attack, heart failure, stroke, kidney failure, loss of vision, and other problems. In addition to taking medication, making lifestyle changes will also help to control your blood pressure. These changes include eating a diet that is low in fat and salt, maintaining a healthy weight, exercising at least 30 minutes most days, not smoking, and using alcohol in moderation.
Verapil , a member of the phenylalkylamine (PAA) subclass of CCB (other members of this subclass include gallopamil and tiapamil) was the first CCB to be discovered and is the only member of this subclass to be widely used in hypertension. 35 Verapil binds to amino acids in the S6 segments in domains III and IV of the α1 subunit of the VGCC. 36 The PAA binding site overlaps with the site to which DHP bind ( Fig. 25.2 ) and binding of Verapil may result in allosteric modulation of DHP binding. 36
Verapil should be stored at room temperature 15 C - 30 C (59 F - 86 F) in a tight, light- resistant container.
The effect of Verapil on AV conduction and the SA node may cause asymptomatic first-degree AV block and transient bradycardia, sometimes accompanied by nodal escape rhythms. PR-interval prolongation is correlated with Verapil plasma concentrations, especially during the early titration phase of therapy. Higher degrees of AV block, however, were infrequently (0.8%) observed in previous Verapil clinical trials. Marked first-degree block or progressive development to second- or third-degree AV block requires a reduction in dosage or, in rare instances, discontinuation of Verapil HCl and institution of appropriate therapy, depending upon the clinical situation.
Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
Some products that may interact with this drug include: aliskiren, clonidine, disopyramide, dofetilide, dolasetron, fingolimod, lithium.
Other medications can affect the removal of Verapil from your body, which may affect how Verapil works. Examples include erythromycin, rifamycins (such as rifampin), ritonavir, St. John's wort, among others.
Verapil can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include asunaprevir, colchicine, flibanserin, ivabradine, lomitapide, midazolam, triazolam, among others.
Some products have ingredients that could raise your heart rate or blood pressure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen).
Verapil has been given concomitantly with short- and long-acting nitrates without any undesirable drug interactions. The pharmacologic profile of both drugs and clinical experience suggest beneficial interactions.
The interaction between cimetidine and chronically administered Verapil has not been studied. Variable results on clearance have been obtained in acute studies of healthy volunteers; clearance of Verapil was either reduced or unchanged.
Increased sensitivity to the effects of lithium (neurotoxicity) has been reported during concomitant Verapil-lithium therapy; lithium levels have been observed sometimes to increase, sometimes to decrease, and sometimes to be unchanged. Patients receiving both drugs must be monitored carefully.
Verapil therapy may increase carbamazepine concentrations during combined therapy. This may produce carbamazepine side effects such as diplopia, headache, ataxia, or dizziness.
Therapy with rifampin may markedly reduce oral Verapil bioavailability.
Phenobarbital therapy may increase Verapil clearance.
Verapil therapy may increase serum levels of cyclosporine.
Verapil may inhibit the clearance and increase the plasma levels of theophylline.
Animal experiments have shown that inhalation anesthetics depress cardiovascular activity by decreasing the inward movement of calcium ions. When used concomitantly, inhalation anesthetics and calcium channel blocking agents, such as Verapil, should each be titrated carefully to avoid excessive cardiovascular depression.
Neuromuscular Blocking Agents
Clinical data and animal studies suggest that Verapil may potentiate the activity of neuromuscular blocking agents (curare-like and depolarizing). It may be necessary to decrease the dose of Verapil and/or the dose of the neuromuscular blocking agent when the drugs are used concomitantly.
Hypotension and bradyarrhythmias have been observed in patients receiving concurrent telithromycin, an antibiotic in the ketolide class.
Sinus bradycardia resulting in hospitalization and pacemaker insertion has been reported in association with the use of clonidine concurrently with Verapil. Monitor heart rate in patients receiving concomitant Verapil and clonidine.
Mammalian Target Of Rapamycin (mTOR) Inhibitors
In a study of 25 healthy volunteers with co-administration of Verapil with sirolimus, whole blood sirolimus Cmax and AUC were increased 130% and 120%, respectively. Plasma S-(-) Verapil Cmax and AUC were both increased 50%. Co-administration of Verapil with everolimus in 16 healthy volunteers increased the Cmax and AUC of everolimus by 130% and 250%, respectively. With concomitant use of mTOR inhibitors (e.g., sirolimus, temsirolimus, and everolimus) and Verapil, consider appropriate dose reductions of both medications.