Doxepina
Doxepin
Doxepin hydrochloride
También conocido como: Sinequan · Anten · Aponal · Deptran · Desidoxepin · Doneurin · Doxal · Doxepia · Gilex · Mareen · Quitaxon · Triadapin · Zonalon · Sinepin · doxepini hydrochloridum · NSC-108160 · P3693A · Doxepinum · Doxepin hydrochloride
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 |
|---|---|---|---|---|---|
| Treatment of psychogenic dermatoses | 3-5 mg/kg PO q12h; maximum dose is 150 mg (per dog) q12h | PO | q12h | — | 🌎 NA |
| Treatment of psychogenic dermatoses | 3-5 mg/kg, PO q8-12h. Begin at 3 mg/kg PO q12h for 2 weeks, then increase by 1 mg/kg PO q12h for 2 weeks up to the maximum dosage as needed; if no clinical response after at least 3-4 weeks of therapy, decrease dosage by 1 mg/kg PO q12h for 2 weeks until at the initial dosage | PO | q8-12h | Titrated over weeks | 🌎 NA |
| Antihistaminic effects in treatment of atopy | 2.2 mg/kg PO three times daily | PO | TID | — | 🌎 NA |
| Antihistaminic effects in treatment of atopy | 3-5 mg/kg twice daily | PO | BID | — | 🌎 NA |
| Antihistaminic effects in treatment of atopy | 0.5-2 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| Antihistaminic effects in treatment of atopy | 1-2 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| Treatment of behavior problems (OCD) | 0.5-1 mg/kg PO twice daily | PO | BID | — | 🌎 NA |
| Treatment of behavior problems (acral lick granulomas) | 3-5 mg/kg PO q12h (up to 150 mg per dog) | PO | q12h | — | 🌎 NA |
- Antihistaminic effects in treatment of atopy: Used especially if dog has anxiety or other behavioral condition
- Antihistaminic effects in treatment of atopy: May be best in nervous or highly strung dogs
- Treatment of behavior problems (acral lick granulomas): Doses as above for psychogenic dermatoses
Gatos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Treatment of psychogenic dermatoses | 0.5-1 mg/kg PO q12-24h. Up to 25-50 mg (total dose) per cat. | PO | q12-24h | Allow 3-4 weeks for initial trial | 🌎 NA |
| Excessive grooming | 0.5-1 mg/kg PO q12h. | PO | q12h | — | 🌎 NA |
| Treatment of behavior problems (e.g., overgrooming, intercat aggression) | 0.5-1 mg/kg PO once to twice daily. | PO | SID to BID | — | 🌎 NA |
Aves
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Treatment of anxiety, pruritus caused feather plucking in psittacines | 1-2 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
| Treatment of anxiety, pruritus caused feather plucking in psittacines | 0.5-1 mg/kg PO twice daily | PO | BID | — | 🌎 NA |
Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.
Resumen
La doxepina es un antidepresivo tricíclico (ATC) derivado de la dibenzoxazepina, utilizado principalmente en medicina veterinaria como terapia adyuvante para dermatosis psicógenas, particularmente aquellas con un componente de ansiedad subyacente.
Aunque se clasifica como antidepresivo, posee propiedades antihistamínicas H1 extremadamente potentes, lo que lo convierte en un agente de doble propósito para el manejo del prurito y las afecciones conductuales. Su eficacia como antihistamínico único para la dermatitis atópica es objeto de debate, pero es altamente valioso cuando el prurito se ve exacerbado por, o conduce a, ansiedad y comportamientos compulsivos (p. ej., granulomas por lamido acral, acicalamiento excesivo).
Perla Clínica: Debido a sus efectos combinados ansiolíticos y antihistamínicos, la doxepina se selecciona a menudo para pacientes nerviosos o muy tensos que padecen enfermedades cutáneas alérgicas.
Mecanismo de acción
Doxepin exerts its effects through multiple receptor pathways:
- Monoamine Reuptake Inhibition: In the central nervous system, doxepin blocks the presynaptic reuptake of norepinephrine (moderate inhibition) and serotonin (5-HT) (weak inhibition) → increasing their synaptic concentrations and prolonging their activity, which contributes to its antidepressant and anxiolytic effects.
- Receptor Antagonism: It exhibits potent H1-histamine receptor blockade (providing anti-pruritic and sedative effects), as well as anticholinergic (muscarinic) and alpha-1 adrenergic blocking activity. These latter receptor affinities are largely responsible for its side effect profile (e.g., dry mouth, urinary retention, hypotension).
Seguridad y advertencias
Contraindicaciones
- Prior sensitivity to doxepin or other tricyclic antidepressants
- Concomitant use with Monoamine Oxidase Inhibitors (MAOIs) such as selegiline or amitraz (within 14 days)
- Urinary retention
- Glaucoma
- Severe cardiac disease
- History of seizures
- Concurrent use with MAOIs
Efectos adversos
- Hyperexcitability (paradoxical)
- Gastrointestinal distress
- Lethargy and sedation
- Ventricular arrhythmias (particularly in overdose)
- Anticholinergic effects (dry mouth, urinary retention, constipation)
- Altered blood glucose levels
- Dry mouth (xerostomia)
- Tachycardia
Precauciones
Pregnancy & Nursing: Safety during pregnancy has not been established (FDA Category C). Doxepin and its active metabolite distribute into milk; use with caution in nursing patients as sedation and respiratory depression have been reported in human infants.
Cardiac Effects: Tricyclics can widen QRS complexes, prolong PR intervals, and invert or flatten T-waves on ECG. Use with caution in patients with pre-existing cardiac disease.
Laboratory Alterations: May alter (increase or decrease) blood glucose levels.
Interacciones farmacológicas
Additive anticholinergic effects; use cautiously.
May inhibit tricyclic antidepressant metabolism and increase the risk of toxicity.
Additive CNS depression; use cautiously.
Increased risk for serotonin syndrome.
Concomitant use (within 14 days) is generally contraindicated due to high risk of serotonin syndrome.
Increased risk for QTc interval prolongation and tricyclic adverse effects.
Increased risk for serotonin syndrome.
May increase the risk of cardiac effects (arrhythmias, hypertension, hyperpyrexia).
Risk of fatal serotonin syndrome
Increased risk of serotonin syndrome
Monitorización
- Efficacy (reduction in pruritus, anxiety, or compulsive behaviors)
- Adverse effects (GI distress, lethargy, hyperexcitability)
- ECG (if arrhythmias are suspected or in cases of overdose)
- Heart rate and rhythm
- Resolution of pruritus or behavioral signs
- Signs of excessive sedation or anticholinergic effects
Farmacocinética
Vida media
Absorción
Appears to be well absorbed after oral administration.
Distribución
Doxepin and its N-demethylated active metabolite are distributed into milk.
Metabolismo
Extensively metabolized in the liver to an active N-demethylated metabolite.
Eliminación
Excreted primarily via the kidneys as metabolites.
Sobredosis
Overdosage with tricyclic antidepressants can be life-threatening.
- Clinical Signs: Severe ventricular arrhythmias, cardiorespiratory collapse, profound CNS depression or seizures.
- Action: Because the toxicities and therapies for treatment are complicated and controversial, it is highly recommended to contact an animal poison control center immediately for further information in any potential overdose situation.
Productos disponibles
Formulaciones
- Capsules: 10 mg, 25 mg, 50 mg, 75 mg, 100 mg, 150 mg
- Oral Concentrate: 10 mg/mL
- Oral capsule (25 mg, 50 mg)
- Topical cream
Etiquetado para humanos
- Doxepin Capsules: 10 mg, 25 mg, 50 mg, 75 mg, 100 mg & 150 mg (Sinequan, generic)
- Doxepin Oral Concentrate: 10 mg/mL in 120 mL (generic)
- Sinepin capsules (25 mg, 50 mg)
- Sinequan capsules
- Zonalon cream
Estado regulador
POM (Prescription Only Medicine) status.
POM (Prescription Only Medicine) status.
Sin datos reguladores para: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Almacenamiento y estabilidad
Store protected from direct sunlight in tight, light-resistant containers at room temperature.
Información para el cliente
- La paciencia es clave: Pueden ser necesarias varias semanas (a menudo 3-4 semanas) antes de observar una eficacia conductual o dermatológica notable. Continúe administrando la dosis exactamente como se le recetó.
- La seguridad es lo primero: Todos los antidepresivos tricíclicos deben dispensarse en envases a prueba de niños y mantenerse fuera del alcance de niños y mascotas. Las sobredosis pueden ser fatales.
- No suspenda el tratamiento abruptamente: Consulte a su veterinario antes de interrumpir la medicación para evitar posibles efectos de abstinencia.
- Monitoree los efectos secundarios: Comuníquese con su veterinario si su mascota presenta letargo extremo, hiperactividad inesperada, vómitos o signos de latidos cardíacos rápidos/irregulares.
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.