Alopurinol
Allopurinol
1,5-dihydro-4H-pyrazolo[3,4-d]pyrimidin-4-one
También conocido como: Zyloprim · Aloprim · Zyloric · Zylapour · allopurinolum · BW-56-158 · HPP · NSC-1390 · oxypurinol (active metabolite) · alloxanthine
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 |
|---|---|---|---|---|---|
| Urate uroliths (dissolution) | 15 mg/kg PO q12h; only in conjunction with low purine foods. | PO | q12h | — | 🌎 NA |
| Urate uroliths (prevention) | 10-20 mg/kg/day | PO | Daily | — | 🌎 NA |
| Urate uroliths (dissolution and prevention) | 7-10 mg/kg PO three times daily | PO | TID | — | 🌎 NA |
| Leishmaniasis (First line treatment) | 10 mg/kg PO twice daily | PO | BID | 6-12 months | 🌎 NA |
| Leishmaniasis (Second line treatment) | 10 mg/kg PO twice daily | PO | BID | 6-12 months | 🌎 NA |
| Leishmaniasis | 20 mg/kg PO q12h | PO | q12h | 9 months | 🌎 NA |
| Leishmaniasis (Alternate protocol alone) | 10 mg/kg PO q8h or 10-20 mg/kg PO q12h | PO | q8h or q12h | 1-4 months | 🌎 NA |
| Leishmaniasis | 10 mg/kg PO twice daily | PO | BID | — | 🌎 NA |
| Leishmaniasis (with renal insufficiency) | 5 mg/kg PO twice daily | PO | BID | — | 🌎 NA |
| Leishmaniasis | 15 mg/kg PO twice daily | PO | BID | months | 🌎 NA |
| Uric acid urolithiasis (Dissolution) | 10 mg/kg p.o. q8h or 15 mg/kg p.o. q12h | PO | q8h or q12h | up to 4 weeks | 🌍 EU |
| Uric acid urolithiasis (Prevention) | 10-15 mg/kg | PO | q24h | — | 🌍 EU |
| Leishmaniosis | 10 mg/kg | PO | q12h | at least 6-12 months | 🌍 EU |
- Urate uroliths (prevention): Preferable to minimize recurrence with dietary therapy to avoid xanthine uroliths.
- Urate uroliths (dissolution and prevention): Goal is to reduce urine urate:creatinine ratio by 50%.
- Leishmaniasis (First line treatment): Used plus Meglumine antimoniate 75-100 mg/kg once daily for 4-8 weeks.
- Leishmaniasis (Second line treatment): Used plus Miltofosine 2 mg/kg PO once daily for 4 weeks OR allopurinol alone.
- Leishmaniasis: With Meglumine antimoniate (100 mg/kg/day SQ) until resolution.
- Leishmaniasis: If possible use with meglumine antimoniate, if not, use alone.
- Leishmaniosis: Use with meglumine antimonate for 1-2 months, or miltefosine for 1 month (NB: this does not result in complete parasitological cure).
Gatos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Leishmaniosis | 10-20 mg/kg | PO | q12-24h | — | 🌍 EU |
- Leishmaniosis: Has been shown to be effective (although experience is limited in this species).
Aves
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Gout (budgies and cockatiels) | Crush one 100 mg tablet into 10 mL of water. Add 20 drops of this solution to one ounce of drinking water. | PO | Continuous in water | — | 🌎 NA |
| Gout (parakeets) | Crush one 100 mg tablet into 10 mL of water. Add 20 drops of this solution to one ounce of drinking water or give 1 drop 4 times daily. | PO | Continuous or QID | — | 🌎 NA |
Reptiles
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Elevated uric acid levels in renal disease (lizards) | 20 mg/kg PO once daily | PO | SID | — | 🌎 NA |
| Gout | 20 mg/kg PO once daily | PO | SID | — | 🌎 NA |
| Hyperuricemia (green iguanas) | 25 mg/kg PO daily | PO | SID | — | 🌎 NA |
- Gout: Suggested dosage based upon human data as dose is not established for reptiles.
Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.
Resumen
Alopurinol es un potente inhibidor de la xantina oxidasa ampliamente utilizado en medicina veterinaria.
Las aplicaciones clínicas clave incluyen:
- Urolitiasis por uratos: Se utiliza principalmente en perros (especialmente en razas predispuestas como los dálmatas) para disolver y prevenir los cálculos de ácido úrico. Debe combinarse con una dieta baja en purinas para prevenir la formación de cálculos de xantina.
- Leishmaniosis canina: Actúa como un agente leishmaniostático. A menudo se utiliza en combinación con antimoniato de meglumina o miltefosina para el manejo a largo plazo.
- Medicina de aves y reptiles: Se utiliza para controlar la hiperuricemia y tratar la gota en aves y reptiles.
Nota clínica: Debido a que el alopurinol aumenta la excreción urinaria de xantina, las dosis altas prolongadas sin restricción dietética de purinas pueden provocar paradójicamente la formación de urolitos de xantina.
Mecanismo de acción
Allopurinol and its primary active metabolite, oxypurinol (alloxanthine), competitively inhibit the enzyme xanthine oxidase.
- Normal Pathway: Hypoxanthine → xanthine oxidase → Xanthine → xanthine oxidase → Uric Acid
- Inhibition: By blocking this enzyme, allopurinol prevents the conversion of oxypurines to uric acid. This decreases serum and urine concentrations of uric acid, while increasing the levels of the more water-soluble precursors (hypoxanthine and xanthine).
In Leishmaniasis: Allopurinol acts as a purine analogue. Leishmania organisms mistakenly incorporate allopurinol metabolites into their RNA, which disrupts protein synthesis and inhibits parasite multiplication.
Seguridad y advertencias
Contraindicaciones
- Known hypersensitivity to allopurinol
- Red-tailed hawks (anecdotal reports of severe toxicity)
Efectos adversos
- Xanthine urolithiasis (especially with high doses or non-restricted diets)
- Hypersensitivity reactions (rash, erythema)
- Lethargy
- Gastrointestinal upset
- Hepatotoxicity (rare)
- Bone marrow suppression (rare)
Precauciones
Prolonged high doses of allopurinol may result in xanthine uroliths; it is highly recommended to use concurrently with a low-purine diet for urolith management. Use with caution and consider dose reduction (e.g., 5 mg/kg PO twice daily) in patients with renal insufficiency.
Interacciones farmacológicas
May increase risks for hypoglycemia and hepato-renal reactions
Increased bone marrow depression may occur
Allopurinol may increase cyclosporine levels
Can increase uric acid levels, antagonizing allopurinol's effect
Allopurinol may reduce the metabolism of warfarin thereby increasing its effect
Thrombocytopenia has occurred in a few human patients when used concurrently
May increase the renal excretion of oxypurinol and thereby reduce xanthine oxidase inhibition; additive effects on blood uric acid may be beneficial
May reduce the solubility of uric acid in the urine and induce urolithiasis
Allopurinol inhibits the metabolism of azathioprine, leading to severe, potentially fatal myelosuppression.
Allopurinol inhibits the metabolism of mercaptopurine, significantly increasing toxicity risk.
Concurrent use increases the risk of cutaneous rash.
May decrease theophylline clearance, increasing the risk of toxicity.
May increase the risk of allopurinol hypersensitivity and toxicity.
Increased risk of skin rashes when used concurrently.
Monitorización
- Urine uric acid (for urolithiasis)
- Adverse effects (rash, lethargy)
- Periodic CBC, liver and renal function tests (e.g., BUN, Creatinine, liver enzymes); especially early in therapy
Farmacocinética
Absorción
Rapidly absorbed following oral administration.
Distribución
Widely distributed in tissue fluid; not highly bound to plasma proteins.
Metabolismo
Rapidly oxidized to its primary active metabolite, oxypurinol (alloxanthine), which is also a xanthine oxidase inhibitor.
Eliminación
Excreted primarily in the urine as oxypurinol and unchanged allopurinol.
Sobredosis
Information on acute overdosage in veterinary species is limited. Massive overdoses may cause gastrointestinal distress (vomiting, diarrhea). Treatment should consist of supportive care and monitoring of renal function. Adequate hydration is important to promote diuresis and excretion.
Productos disponibles
Formulaciones
- Oral tablets
- Powder for injection (lyophilized)
- Compounded oral suspension
Etiquetado para humanos
- Allopurinol Oral Tablets: 100 mg & 300 mg; Zyloprim® (Faro); generic
- Allopurinol Powder for Injection, lyophilized: 500 mg preservative-free in 30 mL vials; Aloprim® (Nabi); generic (Bedford Labs)
Estado regulador
Approved in several EU member states specifically for canine leishmaniosis.
Used under the cascade where specific veterinary licensed products are unavailable.
Sin datos reguladores para: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Almacenamiento y estabilidad
Tablets should be stored at room temperature in well-closed containers; stable in light and air. Powder for injection should be stored at 25°C (excursions permitted to 15-30°C). Once diluted to ≤6 mg/mL, store at room temperature and use within 10 hours; do not refrigerate. Compounded oral suspensions (20 mg/mL) in Ora-Plus/Ora-Sweet retain >95% potency for 60 days at 5°C and 25°C and should be protected from light.
Información para el cliente
Importante: A menos que su veterinario indique lo contrario, administre este medicamento después de las comidas (generalmente alrededor de 1 hora después) para minimizar las molestias estomacales.
- Manejo dietético: Si su mascota está siendo tratada por cálculos de urato, siga estrictamente la dieta baja en purinas prescrita por su veterinario. Administrar este medicamento sin la dieta adecuada puede provocar la formación de un tipo diferente de cálculo (xantina).
- Cuándo llamar al veterinario: Notifique a su veterinario de inmediato si su animal desarrolla una erupción cutánea, se muestra inusualmente letárgico o parece enfermo.
- Asegúrese de que su mascota siempre tenga acceso a abundante agua fresca para ayudar a limpiar el sistema urinario.
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.