VetSheet

Verapamilo

Verapamil

Verapamil hydrochloride

Bloqueador de los canales de calcio / Antiarrítmico de Clase IVPOIVSCPerrosGatosPequeños mamíferosCaballos

También conocido como: Calan · Isoptin · Verelan · Covera-HS · Securon · CP-16533-1 · D-365 · iproveratril hydrochloride · verapamili hydrochloridum

Revisado por el equipo veterinario de VetSheetActualizado 5 abr 2026Referencia veterinaria basada en la evidencia

Initial dose of 0.05 mg/kg IV slowly, can repeat every 5 minutes up to a total dose of 0.15-0.2 mg/kg; Oral Dose: 0.5-2 mg/kg PO q8hIV/PO· q8h (for PO)
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Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.

Dosis por especie

🌎 NA — North America🌍 EU — Europe

Perros

IndicaciónDosisVíaFrecuenciaDuraciónRegión
Supraventricular tachycardiaInitial dose of 0.05 mg/kg IV slowly, can repeat every 5 minutes up to a total dose of 0.15-0.2 mg/kg; Oral Dose: 0.5-2 mg/kg PO q8hIV/POq8h (for PO)🌎 NA
Treatment of hypertension1-5 mg/kg PO q8hPOq8h🌎 NA
Emergency treatment for hemodynamically unstable and sustained (continuous) supraventricular tachycardia0.05 mg/kg boluses IV (slowly) up to a total dose of 0.15 mg/kgIVSeries of boluses🌎 NA
General arrhythmias1-5 mg/kg PO three times daily; 0.05-0.25 mg/kg IV slowlyPO/IVTID (for PO)🌎 NA
Acute termination of supraventricular tachycardiaInitial dose of 0.05 mg/kg should be administered over 1-2 minutes while ECG is monitored; if not effective, may repeat in 5-10 minutes. If arrhythmia still not terminated, may give one last dose of 0.05 mg/kg (total = 0.15 mg/kg). For longer control, may give as a CRI at 2-10 micrograms/kg/minute.IVPRN / CRI🌎 NA
Supraventricular tachyarrhythmias0.5-3 mg/kgPOq8h🌍 EU
Supraventricular tachyarrhythmias (Acute)0.05 mg/kgIVonceover 5 minutes🌍 EU
  • Emergency treatment for hemodynamically unstable and sustained (continuous) supraventricular tachycardia: As an alternative to diltiazem
  • Acute termination of supraventricular tachycardia: Effect may persist for 30 minutes or less.
  • Supraventricular tachyarrhythmias (Acute): Administer slowly with ECG monitoring. Up to 4 repeat IV administrations at a reduced dose of 0.025 mg/kg q5min if necessary.

Gatos

IndicaciónDosisVíaFrecuenciaDuraciónRegión
Supraventricular tachycardiaInitial dose of 0.025 mg/kg IV slowly, can repeat every 5 minutes up to a total dose of 0.15-0.2 mg/kg; Oral Dose: 0.5-1 mg/kg PO q8hIV/POq8h (for PO)🌎 NA
Supraventricular tachyarrhythmias0.5-1 mg/kgPOq8h🌍 EU
Supraventricular tachyarrhythmias (Acute)0.025 mg/kgIVonceover 5 minutes🌍 EU
  • Supraventricular tachyarrhythmias (Acute): Administer slowly with ECG monitoring. Up to 3 repeat IV administrations q5min if necessary.

Pequeños mamíferos

IndicaciónDosisVíaFrecuenciaDuraciónRegión
Cardiovascular disease0.25-0.5 mg (total dose per hamster) SCSC🌎 NA
Cardiovascular disease8-16 mg/kg PO + 0.5-2 mg/kg SC once daily (q24h)PO/SCq24h🌎 NA
  • Cardiovascular disease: Hamsters
  • Cardiovascular disease: Rabbits

Caballos

IndicaciónDosisVíaFrecuenciaDuraciónRegión
To control ventricular rate in atrial fibrillation0.025-0.05 mg/kg IV q 30 minutes; give less than 0.2 mg/kg total doseIVq 30 minutes🌎 NA
  • To control ventricular rate in atrial fibrillation: ARCI UCGFS CLASS 4 DRUG

Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.

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Resumen

El verapamilo es un bloqueador de los canales de calcio no dihidropiridínico y un agente antiarrítmico de Clase IV.

A diferencia de los bloqueadores de los canales de calcio dihidropiridínicos (como el amlodipino), que actúan principalmente sobre el músculo liso vascular para causar vasodilatación, el verapamilo tiene efectos profundos sobre el sistema de conducción cardíaca, específicamente sobre el nodo auriculoventricular (AV).

​Usos clínicos clave:​

  • Utilizado principalmente en medicina veterinaria para controlar las ​taquicardias supraventriculares (TSV)​ en perros y gatos.
  • Puede utilizarse para el control de la frecuencia en el aleteo auricular o la fibrilación auricular.
  • ​Perla clínica:​ El verapamilo es un inhibidor conocido de la ​glucoproteína P (P-gp)​. Debido a este mecanismo, actualmente se está investigando como tratamiento adyuvante para la epilepsia farmacorresistente para ayudar a prevenir la salida de fármacos antiepilépticos del sistema nervioso central.

Mecanismo de acción

Verapamil exerts its effects by blocking the transmembrane influx of extracellular calcium ions through L-type voltage-gated calcium channels in myocardial cells and vascular smooth muscle cells.

  • ​Cardiac Conduction (Primary Effect):​ Blocks calcium channels in the SA and AV nodes → decreases AV node conduction velocity and increases the effective refractory period → slows ventricular response rate in supraventricular arrhythmias.
  • ​Myocardial Contractility:​ Exhibits a negative inotropic effect (decreases heart muscle contractility).
  • ​Vascular Smooth Muscle:​ Inhibits contractile mechanisms → causes vasodilation and decreases peripheral vascular resistance (though less potently than amlodipine).
  • ​Neurological:​ Inhibits ​P-glycoprotein (MDR1/ABCB1)​ at the blood-brain barrier → reduces the efflux of certain substrate drugs back into the systemic circulation.

Seguridad y advertencias

Contraindicaciones

  • Cardiogenic shock
  • Severe CHF (unless secondary to a supraventricular tachycardia amenable to verapamil)
  • Hypotension (<90 mmHg systolic)
  • Sick sinus syndrome
  • 2nd or 3rd degree AV block
  • Digoxin intoxication
  • Hypersensitivity to verapamil
  • Recent use (within a few hours) of IV beta-adrenergic blockers
  • Left ventricular dysfunction
  • Heart failure

Efectos adversos

  • Hypotension
  • Bradycardia
  • Tachycardia
  • Exacerbation of congestive heart failure (CHF)
  • Peripheral edema
  • AV block
  • Pulmonary edema
  • Nausea
  • Constipation
  • Dizziness
  • Headache
  • Fatigue
  • Precipitation or exacerbation of congestive heart failure

Precauciones

​Critical Warning:​ IV verapamil is contraindicated within a few hours of IV beta-adrenergic blocking agents (e.g., propranolol). The combination can severely depress myocardial contractility and AV node conduction, potentially causing rapid hemodynamic deterioration and ventricular fibrillation.

  • ​Cardiac Disease:​ Use with caution in patients with heart failure or hypertrophic cardiomyopathy (HCM) due to negative inotropic effects.
  • ​Organ Impairment:​ Toxicity may be potentiated in patients with hepatic or renal impairment.
  • ​Arrhythmias:​ Use very cautiously in patients with atrial fibrillation and Wolff-Parkinson-White (WPW) syndrome as fatal arrhythmias may result.
  • ​Endocrine:​ May increase blood glucose in dogs; use with caution in diabetic animals.
  • ​Breed Sensitivities:​ Verapamil is a neurotoxic substrate of P-glycoprotein. Use with extreme caution in herding breeds (e.g., Collies, Australian Shepherds) that may possess the MDR1 (ABCB1) gene mutation causing a nonfunctional P-gp protein.

Interacciones farmacológicas

ACE Inhibitors

May cause additive hypotensive effects

Alpha-Adrenergic Blockers (e.g., prazosin)

May cause additive hypotensive effects

Beta-Adrenergic Blockers (e.g., propranolol)

May cause additive negative cardiac inotrope and chronotrope effects; IV combination is contraindicated

Doxorubicin

Verapamil may increase doxorubicin concentrations

COPP Chemotherapy

May decrease oral absorption of verapamil

Cyclosporine

Verapamil may increase cyclosporine levels

Dantrolene

Cardiovascular collapse reported in animals when used with verapamil

DigoxinMajor

Verapamil may increase blood levels of digoxin; monitoring recommended

Disopyramide

May cause additive effects and impair left ventricular function; concurrent use within 24-48 hours not recommended

Diuretics

May cause additive hypotensive effects

Erythromycin, Clarithromycin

May increase verapamil levels

Flecainide

Possible additive effects; concurrent use is to be avoided in humans

Neuromuscular Blockers

Effects of nondepolarizing muscle relaxants may be enhanced by verapamil

Phenobarbital

May reduce verapamil levels

Quinidine

Additive alpha-adrenergic blocking activity; increased hypotensive effect; verapamil can block quinidine's AV conductive effects and increase quinidine levels

Rifampin

May reduce verapamil levels

TheophyllineMajor

Verapamil may increase serum levels of theophylline and lead to toxicity

VincristineModerate

Calcium channel blockers may increase intracellular vincristine by inhibiting the drug's outflow from the cell

Beta-blockersMajor

Profound negative inotropic and chronotropic effect

Sodium-channel blockersMajor

May lead to cardiovascular depression and hypotension

Vitamin D or Calcium saltsModerate

May adversely affect verapamil activity

CimetidineModerate

May increase the effects of verapamil

DigitoxinMajor

May increase blood levels leading to potentially toxic effects

Non-depolarizing muscle relaxantsModerate

Neuromuscular blocking effects may be enhanced

Monitorización

  • Clinical signs of toxicity (hypotension, bradycardia, edema)
  • Blood pressure (especially during acute IV therapy)
  • Serum concentration (if efficacy or toxicity warrant; 100-300 ng/mL is considered therapeutic)
  • ECG (especially during IV administration)
  • Heart rate and rhythm
  • Liver function (in patients with hepatic disease)

Farmacocinética

Vida media

Perros0.8 - 2.5 hours

Absorción

Rapidly absorbed after oral administration (~90%), but undergoes a high first-pass effect in the liver, resulting in systemic bioavailability of only 20-30%. Hepatic dysfunction can significantly increase bioavailability. Food decreases the rate and extent of absorption of sustained-release tablets.

Distribución

Volume of distribution is approximately 4.5 L/kg in dogs. Highly protein-bound (~90% in humans). Crosses the placenta and enters milk at levels approaching plasma concentrations.

Metabolismo

Extensively metabolized in the liver to at least 12 separate metabolites, with norverapamil being the predominant active metabolite.

Eliminación

The majority of metabolites are excreted in the urine. Only 3-4% is excreted unchanged in the urine.

Sobredosis

​Clinical Signs of Overdose:​ Bradycardia, hypotension, hyperglycemia, junctional rhythms, and 2nd or 3rd degree AV block.

​Treatment:​

  • ​Decontamination:​ If secondary to recent oral ingestion, consider gut emptying and activated charcoal administration.
  • ​Supportive Care:​ Vigorously monitor cardiac and respiratory function.
  • ​Negative Inotropy:​ Intravenous calcium salts (1 mL of 10% solution per 10 kg of body weight) may treat negative inotropic signs, but may not adequately resolve heart block.
  • ​Hypotension:​ Fluid therapy and pressor agents (e.g., dopamine, norepinephrine) may be utilized.
  • ​AV Block / Bradycardia:​ Treat with isoproterenol, norepinephrine, atropine, or cardiac pacing.
  • ​Rapid Ventricular Rate:​ Patients developing rapid ventricular rate due to antegrade conduction in flutter/fibrillation with WPW syndrome have been treated with D.C. cardioversion, lidocaine, or procainamide.

Productos disponibles

Formulaciones

  • Sustained/Extended-Release Tablets
  • Sustained/Extended-Release Capsules
  • Injection
  • Injectable: 2.5 mg/ml solution
  • Oral: 40 mg, 80 mg, 120 mg, 160 mg tablets
  • Oral: 40 mg/5 ml oral solution

Veterinario

  • None

Etiquetado para humanos

  • Verapamil HCl Tablets: 40 mg, 80 mg & 120 mg (Calan®, generic)
  • Verapamil HCl Sustained/Extended-Release Tablets/Capsules: 100 mg, 120 mg, 180 mg, 200 mg, 240 mg, 300 mg & 360 mg (Calan® SR, Covera-HS®, Isoptin® SR, Verelan®, Verelan® PM, generic)
  • Verapamil HCl for Injection: 2.5 mg/mL in 2 mL & 4 mL vials, amps and syringes (generic)
  • Securon (2.5 mg/ml injectable)
  • Verapamil (40 mg, 80 mg, 120 mg, 160 mg tablets; 40 mg/5 ml oral solution)

Estado regulador

European Union✓ AprobadoMedicamento de prescripciónEMA

Human authorized products used under the cascade.

United Kingdom✓ AprobadoMedicamento de prescripción · POMVMD

POM (Prescription Only Medicine)

Sin datos reguladores para: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU

Almacenamiento y estabilidad

Verapamil HCl tablets should be stored at room temperature (15-30°C). The injectable product should be stored at room temperature (15-30°C) and protected from light and freezing.

Información para el cliente

El verapamilo es un medicamento utilizado principalmente para corregir ritmos cardíacos anormalmente rápidos.

  • ​El cumplimiento es clave:​ Para que sea efectivo, su mascota debe recibir todas las dosis exactamente como las prescribió su veterinario. No omita dosis ni suspenda el medicamento abruptamente.
  • ​Qué observar:​ Comuníquese con su veterinario de inmediato si su mascota se muestra inusualmente letárgica, muestra intolerancia al ejercicio, comienza a jadear, tiene dificultad para respirar o tos, o desarrolla cualquier cambio repentino en su comportamiento o actitud.
  • ​Notas dietéticas:​ Siga las instrucciones de su veterinario sobre si debe administrar este medicamento con o sin alimentos, ya que la comida puede afectar la forma en que se absorben ciertas formulaciones.

La referencia de medicamentos de VetSheet está destinada a profesionales veterinarios autorizados como ayuda para la toma de decisiones clínicas, no como sustituto del criterio profesional ni del prospecto actual del fabricante.