Halotano
Halothane
2-bromo-2-chloro-1,1,1-trifluoroethane
También conocido como: Fluothane · Ineltano · phthorothanum · Halothanum
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 |
|---|---|---|---|---|---|
| General Anesthesia | 3% (induction); 0.5-1.5% (maintenance) | Inhalation | Continuous | As needed for procedure | 🌎 NA |
| General Anesthesia | 0.5-3.5%, inhaled | Inhalation | Continuous | As needed for procedure | 🌎 NA |
| Induction of anaesthesia (unpremedicated) | 3-4% concentration | Inhalational | Continuous | Until induced | 🌍 EU |
| Maintenance of anaesthesia | 0.8-1.0% (MAC) | Inhalational | Continuous | Duration of procedure | 🌍 EU |
- General Anesthesia: Concentrations are dependent upon fresh gas flow rate.
- Induction of anaesthesia (unpremedicated): Delivered via calibrated vaporizer
- Maintenance of anaesthesia: Adjust according to individual requirement and concurrent drugs
Gatos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| General Anesthesia | 3% (induction); 0.5-1.5% (maintenance) | Inhalation | Continuous | As needed for procedure | 🌎 NA |
| General Anesthesia | 0.5-3.5%, inhaled | Inhalation | Continuous | As needed for procedure | 🌎 NA |
| Induction of anaesthesia (unpremedicated) | 3-4% concentration | Inhalational | Continuous | Until induced | 🌍 EU |
| Maintenance of anaesthesia | 0.8-1.0% (MAC) | Inhalational | Continuous | Duration of procedure | 🌍 EU |
- General Anesthesia: Concentrations are dependent upon fresh gas flow rate.
- Induction of anaesthesia (unpremedicated): Delivered via calibrated vaporizer
- Maintenance of anaesthesia: Adjust according to individual requirement and concurrent drugs
Pequeños mamíferos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| General Anesthesia (Mice, Rats, Gerbils, Hamsters, Guinea pigs, Chinchillas) | Induction: 2%-4%, maintenance: 0.25%-2% | Inhalation | Continuous | As needed for procedure | 🌎 NA |
- General Anesthesia (Mice, Rats, Gerbils, Hamsters, Guinea pigs, Chinchillas): Using a non-rebreathing system.
Aves
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| General Anesthesia | 2% (small birds) or 2.5%-3% (large birds) for induction; 0.5%-1.5% for maintenance | Inhalation | Continuous | As needed for procedure | 🌎 NA |
- General Anesthesia: Induction usually occurs in 2-4 minutes. Recovery takes 3-5 minutes. Bradycardia, hypotension, and hypothermia may occur but rapidly resolve upon discontinuation.
Caballos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| General Anesthesia (Draft Horses) | 4%-5% initially, maintenance 2.5%-3% | Inhalation | Continuous | As needed for procedure | 🌎 NA |
- General Anesthesia (Draft Horses): Administered in an oxygen-enriched semi-closed large animal circle system. Reduce as indicated by physical monitoring.
Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.
Resumen
El halotano es un anestésico general inhalatorio halogenado clásico que históricamente fue un pilar en la medicina veterinaria debido a su potencia, controlabilidad y falta de inflamabilidad.
Aunque allanó el camino para la anestesia veterinaria moderna, está en gran medida obsoleto y ya no está disponible comercialmente en muchos países. Ha sido ampliamente reemplazado por agentes más nuevos (como isoflurane, sevoflurane y desflurane) que ofrecen perfiles de seguridad superiores, particularmente con respecto a la depresión cardiovascular y la hepatotoxicidad.
Perlas clínicas:
- El halotano tiene un coeficiente de partición sangre-gas más alto en comparación con los inhalantes modernos, lo que conduce a tiempos de inducción y recuperación más lentos.
- Es conocido de forma única por sensibilizar el miocardio a las catecolaminas, aumentando significativamente el riesgo de arritmias ventriculares.
- Aproximadamente el 12% del fármaco se somete a metabolismo hepático (a diferencia del isoflurane, que es <1%), lo que contribuye a su potencial de hepatotoxicidad mediada por el sistema inmunitario (hepatitis por halotano).
Mecanismo de acción
The exact mechanism of inhalant anesthetics remains incompletely understood, but involves multiple central nervous system targets:
- Lipid Matrix Interaction: Historically explained by the Meyer-Overton rule, halothane interacts with the lipid bilayer of neuronal membranes, disrupting normal ion channel function.
- Receptor Modulation: Modern evidence suggests halothane acts via positive allosteric modulation of inhibitory receptors (such as GABA_A and glycine receptors) → enhancing CNS depression.
- Excitatory Inhibition: It simultaneously inhibits excitatory receptors (such as NMDA and nicotinic acetylcholine receptors) → dampening neuronal excitability.
Systemic Effects:
- Profound CNS depression and blunting of thermoregulatory centers.
- Increased cerebral blood flow.
- Dose-dependent respiratory depression (especially pronounced in ruminants).
- Significant myocardial depression, vasodilation, and hypotension.
Seguridad y advertencias
Contraindicaciones
- History or predilection towards malignant hyperthermia
- Significant hepatotoxicity or unexplained fever/jaundice after previous halothane exposure
- Liver disease
- Patients with a history of malignant hyperthermia
Efectos adversos
- Dose-related hypotension
- Cardiac depression and decreased cardiac output
- Cardiac dysrhythmias (sensitizes myocardium to catecholamines)
- Malignant hyperthermia-stress syndrome (reported in pigs, horses, dogs, cats)
- Hepatotoxicity (jaundice, fatal liver necrosis)
- Respiratory depression
- Hypothermia
- Dose-dependent hypotension
- Bradycardia
- Decreased myocardial contractility
- Reduced hepatic blood flow
- Ventricular arrhythmias
- Neonatal depression (crosses placental barrier)
Precauciones
Hepatotoxicity Warning: Halothane can cause severe, sometimes fatal, liver necrosis. Do not re-expose patients who have previously shown unexplained fever or jaundice following halothane anesthesia.
- Cardiovascular/Neurologic: Use with extreme caution in patients with cardiac arrhythmias, hepatic impairment, increased intracranial pressure (CSF) or head injury, myasthenia gravis, or pheochromocytoma.
- Pregnancy: Categorized as Class C. May be teratogenic; use only when benefits clearly outweigh potential risks.
- Equipment: Halothane vapor can react with aluminum, brass, and lead in the presence of moisture. It also causes rapid deterioration of rubber and some plastics.
Interacciones farmacológicas
Not recommended for post-operative analgesia in patients that have received halothane anesthesia due to increased risk of hepatotoxicity.
Can decrease requirements of halothane by up to 40%.
Use with caution; additive neuromuscular blockade may occur.
Use with caution; additive neuromuscular blockade may occur.
Additive neuromuscular blockade may occur.
May induce increased incidences of cardiac effects (bradycardia, arrhythmias, sinus arrest, apnea) and malignant hyperthermia in susceptible patients.
Halothane sensitizes the myocardium to catecholamines; severe ventricular arrhythmias may result. Use with extreme caution at reduced doses.
May cause significant hypotension if used with halothane.
Reduces the concentration of halothane required to achieve surgical anaesthesia
Reduces the concentration of halothane required to achieve surgical anaesthesia
Reduces the concentration of halothane required to achieve surgical anaesthesia
Facilitates the generation of ventricular arrhythmias
Monitorización
- Respiratory and ventilatory status
- Cardiac rate and rhythm (ECG is highly recommended due to arrhythmogenic potential)
- Blood pressure (especially in 'at risk' patients)
- Level of anesthetic depth
- Body temperature (monitor for hypothermia or malignant hyperthermia)
- Heart rate and rhythm (ECG)
- Respiratory rate and depth
- Capnography (ETCO2)
- Anaesthetic depth (jaw tone, palpebral reflex)
Farmacocinética
Absorción
Rapidly absorbed through the lungs into the systemic circulation.
Distribución
Highly lipid soluble; distributes widely into tissues including the CNS. Distributed into milk.
Metabolismo
Approximately 12% of the absorbed drug is metabolized by the liver to trifluoroacetic acid, chlorine, and bromine radicals.
Eliminación
The bulk of the absorbed drug is re-excreted by the lungs and eliminated with expired air. Hepatic metabolites are excreted in the urine.
Sobredosis
Overdosage of halothane results in profound cardiopulmonary depression, characterized by severe hypotension, bradycardia, arrhythmias, and apnea.
Treatment:
- Immediately turn off the anesthetic vaporizer.
- Flush the breathing circuit with 100% oxygen.
- Institute positive pressure ventilation.
- Provide cardiovascular support (e.g., IV fluid volume expansion, positive inotropes like dobutamine, and anticholinergics for bradycardia).
- Lidocaine may be required to treat halothane-induced ventricular dysrhythmias.
Productos disponibles
Formulaciones
- Inhalation liquid (vaporized for administration)
- Inhalational liquid: 250 ml bottle
Veterinario
- Fluothane 250 ml bottle
- Halothane POM-V 250 ml bottle
Estado regulador
POM-V classification.
POM-V classification.
Sin datos reguladores para: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Almacenamiento y estabilidad
Store below 40°C in a tight, light-resistant container. Halothane stability is maintained by the addition of thymol and ammonia. Thymol does not vaporize and may accumulate in the vaporizer, causing a yellow discoloration (do not use discolored solutions). In the presence of moisture, halothane vapor reacts with aluminum, brass, and lead. It also causes rapid deterioration of rubber and some plastics.
Información para el cliente
El halotano es un gas anestésico inhalado que se utiliza para mantener a los animales inconscientes y sin dolor durante la cirugía.
- Uso moderno: Aunque fue muy común en el pasado, los hospitales veterinarios hoy en día utilizan principalmente gases anestésicos más nuevos y seguros. Si se utiliza halotano, su veterinario ha determinado que es apropiado para la situación específica de su mascota.
- Riesgos: Como todos los anestésicos generales, conlleva riesgos como caídas en la presión arterial, cambios en el ritmo cardíaco y disminución de la temperatura corporal. Su equipo veterinario monitoreará de cerca los signos vitales de su mascota durante todo el procedimiento.
- Post-anestesia: Su mascota puede estar aturdida o somnolienta durante uno o dos días después de llegar a casa. Manténgala en un ambiente cálido, tranquilo y seguro mientras se recupera.
- Advertencia: Informe a su veterinario si su mascota ha tenido alguna vez una mala reacción a la anestesia en el pasado, particularmente fiebres inexplicables o problemas hepáticos.
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.