Ranitidina
Ranitidine
Ranitidine hydrochloride
También conocido como: Zantac 75 · Zantac EFFERdose · AH-19065 · ranitidini hydrochloridum · Ranitidinum
Revisado por el equipo veterinario de VetSheetActualizado 5 abr 2026Referencia veterinaria basada en la evidencia
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
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| For esophagitis | 1-2 mg/kg | PO | twice daily | — | 🌎 NA |
| For chronic gastritis | 0.5 mg/kg | PO | twice daily | — | 🌎 NA |
| For ulcer disease | 0.5-2 mg/kg | PO, IV or IM | q8-12h | — | 🌎 NA |
| For ulcer disease | 2 mg/kg | PO, IV | q8h | — | 🌎 NA |
| For ulcer disease (also used for esophagitis) | 1-2 mg/kg | PO, IV, SC | q12h | — | 🌎 NA |
| For ulcer disease | 2 mg/kg | PO, IV | q12h | — | 🌎 NA |
| For gastrinoma | 1-2 mg/kg | PO, SC, IV | q8-12h | — | 🌎 NA |
| For gastrinoma | 0.5 mg/kg | PO, IV or SC | twice daily | — | 🌎 NA |
| To treat hypergastrinemia secondary to chronic renal failure | 1-2 mg/kg | PO | twice daily | — | 🌎 NA |
| To treat hyperhistaminemia secondary to mast cell tumors | 2 mg/kg | PO/IV/IM/SC | q12h | — | 🌎 NA |
| As a prokinetic agent to stimulate gastric contractions | 1-2 mg/kg | PO | q12h | — | 🌎 NA |
| All uses (ulcers, gastritis, prokinetic) | 2 mg/kg | slow IV, SC, PO | q8-12h | Typically 1 month for ulcers (2 weeks post-remission) | 🌍 EU |
- To treat hyperhistaminemia secondary to mast cell tumors: Route not explicitly specified in this line of monograph, typically PO/injectable
- All uses (ulcers, gastritis, prokinetic): Absorption is not clinically significantly affected by food intake.
Gatos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| For ulcer disease/esophagitis | 2.5 mg/kg IV q12h or 3.5 mg/kg PO q12h | IV, PO | q12h | — | 🌎 NA |
| For ulcer disease/esophagitis | 1-2 mg/kg | PO, IV, SC | q12h | — | 🌎 NA |
| For ulcer disease/esophagitis | 2 mg/kg | PO, IV | q12h | — | 🌎 NA |
| As a prokinetic agent to stimulate colonic motility | 1-2 mg/kg | PO | q8-12h | — | 🌎 NA |
| As a prokinetic agent to stimulate colonic motility | 1-2 mg/kg | PO | q12h | — | 🌎 NA |
| All uses | 2 mg/kg/day | IV | constant infusion | — | 🌍 EU |
| All uses | 2.5 mg/kg | IV | Not specified | — | 🌍 EU |
- All uses: Not an effective acid suppressant in healthy cats.
- All uses: Not an effective acid suppressant in healthy cats.
Pequeños mamíferos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| As a prokinetic in rabbits | 0.5 mg/kg | IV | q24h | — | 🌎 NA |
| For suspected gastric ulceration in rabbits | 2-5 mg/kg | PO | twice daily | — | 🌎 NA |
- As a prokinetic in rabbits: Used with cisapride (0.5 mg/kg PO q8h).
Hurones
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| For Helicobacter mustelae | 24 mg/kg | PO | q8-12h | 14 days | 🌎 NA |
- For Helicobacter mustelae: Uses Ranitidine bismuth citrate (must be compounded). Given with clarithromycin (12.5 mg/kg PO q8-12h).
Caballos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Foals | 1.5 mg/kg IV q8h or 6.6 mg/kg PO q8h | IV, PO | q8h | — | 🌎 NA |
| Foals | 6.6 mg/kg IV q4h or 0.8-2.2 mg/kg IV four times a day; 5-10 mg/kg PO two to four times a day. | IV, PO | q4h or QID (IV); BID-QID (PO) | — | 🌎 NA |
| Adults | 1.5-2 mg/kg IV or IM q6-8h; 6.6 mg/kg PO q8h | IV, IM, PO | q6-8h (IV/IM); q8h (PO) | — | 🌎 NA |
- Foals: Often used with omeprazole (4 mg/kg PO q24h).
Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.
Resumen
Ranitidina es un antagonista competitivo de los receptores H2 de histamina y un agente procinético gastrointestinal utilizado ampliamente en medicina veterinaria.
Características clínicas clave:
- Supresión ácida: Se utiliza para el tratamiento y la profilaxis de úlceras gástricas, abomasales y duodenales, gastritis urémica y gastritis erosiva inducida por fármacos o relacionada con el estrés.
- Actividad procinética: De forma única entre los bloqueadores H2, la ranitidina estimula la motilidad gastrointestinal, lo que la hace útil para el vaciado gástrico retardado y para estimular la actividad colónica en gatos (p. ej., para megacolon).
- Mastocitosis sistémica: Ayuda a controlar las condiciones hipersecretoras asociadas con los tumores de mastocitos (que liberan cantidades masivas de histamina).
Perla clínica: La ranitidina es de 3 a 13 veces más potente que la cimetidina sobre una base molar. Además, tiene significativamente menos interacciones medicamentosas porque no inhibe apreciablemente las enzimas del citocromo P450 hepático, lo que la convierte en una opción más segura para pacientes que reciben múltiples medicamentos.
Mecanismo de acción
Ranitidine exerts its effects via two distinct mechanisms:
- Gastric Acid Suppression: It competitively inhibits histamine at the H2 receptors located on the basolateral membrane of gastric parietal cells.
- Histamine blockade → decreased intracellular cAMP → reduced activation of the H+/K+ ATPase (proton pump) → significant reduction in both basal and stimulated gastric acid and pepsin secretion.
- Prokinetic Effect: It reversibly inhibits acetylcholinesterase (AChE) in the gastrointestinal tract.
- AChE inhibition → decreased breakdown of acetylcholine → increased acetylcholine (ACh) at muscarinic receptors → stimulation of GI smooth muscle motility and increased lower esophageal sphincter pressure.
Seguridad y advertencias
Contraindicaciones
- Hypersensitivity to ranitidine
- No specific contraindications available in the monograph
Efectos adversos
- Vomiting (associated with rapid IV boluses in small animals)
- Pain at the injection site (IM administration)
- Mental confusion (rare, documented in humans)
- Headache (rare, documented in humans)
- Agranulocytosis (rare)
- Transient cardiac arrhythmias (if given too rapidly IV)
- Cardiac arrhythmias (rare, typically with rapid IV)
- Hypotension (rare, typically with rapid IV)
Precauciones
Use cautiously and consider reduced dosages in patients with diminished renal function or hepatic insufficiency, as the drug may accumulate.
Geriatric patients may be more susceptible to adverse effects.
High-dose, chronic IV therapy (longer than 5 days) has caused increased serum ALT levels in humans; monitoring liver enzymes is recommended in these scenarios.
Use with caution in nursing veterinary patients, as ranitidine is excreted in breast milk (milk:plasma ratio of 5:1 to 12:1).
Interacciones farmacológicas
Ranitidine (dose-dependent) may inhibit acetaminophen metabolism.
High doses may decrease the absorption of ranitidine; administer at least 2 hours apart.
Absorption of ketoconazole may be reduced secondary to increased gastric pH.
Absorption of itraconazole may be reduced secondary to increased gastric pH.
Ranitidine may increase metoprolol half-life and peak serum levels.
Ranitidine may increase nifedipine AUC by 30%.
Delays the absorption but increases the peak serum level of ranitidine; relative bioavailability may be increased by 23%.
Long-term ranitidine use may reduce oral absorption of Vitamin B-12.
May affect absorption; advisable to administer sucralfate 2 hours before H2 blockers
Ranitidine may reduce absorption or effect; stagger oral doses by 2 hours
Ranitidine may reduce absorption or effect; stagger oral doses by 2 hours
Monitorización
- Clinical efficacy (resolution of clinical signs, improved appetite, absence of blood in feces/vomitus)
- Endoscopic examination (if indicated for ulcer healing)
- Serum ALT values (consider monitoring during high-dose, chronic IV therapy)
- Resolution of gastrointestinal clinical signs
- Heart rate and blood pressure (during IV administration)
Farmacocinética
Vida media
Absorción
Dogs: Oral bioavailability is ~81%. Horses: Oral bioavailability is ~27% in adults and 38% in foals. Peak levels occur in 100 mins (adults) and 60 mins (foals). Humans: Rapidly absorbed but undergoes extensive first-pass metabolism (net bioavailability ~50%). Food does not appreciably alter absorption.
Distribución
Widely distributed throughout the body. Volume of distribution: 2.6 L/kg (dogs), 1.1 L/kg (adult horses), 1.5 L/kg (foals). Only 10-19% bound to plasma proteins. Distributes into milk at 25-100% of plasma levels.
Metabolismo
Metabolized in the liver to inactive metabolites.
Eliminación
Excreted in the urine by the kidneys via glomerular filtration and tubular secretion. Clearance in horses is ~10 mL/min/kg (adults) and 13.3 mL/min/kg (foals).
Sobredosis
Clinical experience with ranitidine overdosage is limited, but the drug has a wide margin of safety.
- Signs of Toxicity: In laboratory animals, massive doses (225 mg/kg/day) have caused muscular tremors, vomiting, and rapid respirations. Single doses of 1 gram/kg in rodents were not fatal.
- Treatment: Handle using standard protocols for oral drug ingestions (e.g., gastric decontamination if recent and appropriate). Treat clinical signs symptomatically and supportively. Hemodialysis and peritoneal dialysis can effectively remove ranitidine from the body.
Productos disponibles
Formulaciones
- Effervescent oral tablets
- Oral solution
- Injection
- Injectable: 25 mg/ml solution
- Oral: 75 mg tablet
- Oral: 150 mg tablet
- Oral: 300 mg tablet
- Oral: 15 mg/ml syrup
Veterinario
- None (No veterinary-labeled products currently available)
Etiquetado para humanos
- Ranitidine HCl Oral Tablets: 75 mg, 150 mg & 300 mg (Zantac, Zantac 75, generic)
- Ranitidine HCl Effervescent Oral Tablets: 25 mg & 150 mg (Zantac EFFERdose)
- Ranitidine HCl Solution: 15 mg/mL (Zantac, generic)
- Ranitidine HCl Injection: 1 mg/mL (premixed) & 25 mg/mL (Zantac, generic)
- Ranitidine 75 mg, 150 mg, 300 mg tablets
- Ranitidine 15 mg/ml syrup
- Ranitidine 25 mg/ml injectable solution
Estado regulador
POM (Prescription Only Medicine)
POM (Prescription Only Medicine)
Sin datos reguladores para: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Almacenamiento y estabilidad
Store tablets in tight, light-resistant containers at room temperature. Store injectable products protected from light at temperatures less than 30°C. A slight darkening of the injectable solution does not affect potency. Injection is stable up to 48 hours when mixed with commonly used IV solutions (including 5% sodium bicarbonate).
Información para el cliente
Ranitidina es un medicamento utilizado para reducir el ácido estomacal y ayudar a que los alimentos se muevan a través del tracto digestivo de manera más efectiva.
- Administración: Administre este medicamento exactamente como lo recetó su veterinario. No omita dosis, ya que los niveles de ácido estomacal pueden rebotar y los síntomas pueden reaparecer.
- Horario: Puede administrarse con o sin comida. Si su mascota también está tomando antiácidos, adminístrelos con al menos 2 horas de diferencia de la ranitidina.
- Efectos secundarios: La ranitidina es generalmente muy segura y bien tolerada. Los efectos secundarios son raros, pero pueden incluir malestar estomacal leve.
- Almacenamiento: Mantenga las tabletas en un recipiente herméticamente cerrado a temperatura ambiente, lejos de la luz directa.
Nota: Consulte siempre a su veterinario antes de administrar cualquier medicamento o suplemento nuevo, aunque la ranitidina tiene menos interacciones medicamentosas que los antiácidos más antiguos como la cimetidina.
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.