Zidovudina
Zidovudine
3'-azido-2',3'-dideoxythymidine
También conocido como: Retrovir · AZT · ZDV · azidodeoxythymidine · 3'-azido-2',3'-dideoxythymidine · azidothymidine · BW-A509U · BW-509U · compound-S · zidovudinum
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
Gatos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Adjunctive therapy of FeLV and FIV | 5-10 mg/kg PO or SC q12h | PO, SC | q12h | — | 🌎 NA |
| Adjunctive therapy of FeLV and FIV | 5-10 mg PO or SC q12h | PO, SC | q12h | — | 🌎 NA |
| FeLV | 5 mg/kg PO or SC q12h | PO, SC | q12h | — | 🌎 NA |
| FIV encephalopathy | 20 mg/kg PO q12h | PO | q12h | — | 🌎 NA |
- Adjunctive therapy of FeLV and FIV: Higher dose should be used carefully as side effects can develop. For SC injection, dilute lyophilized product in isotonic sodium chloride to prevent local irritation. For PO, syrup or gelatin capsules can be used.
- Adjunctive therapy of FeLV and FIV: Note: Dose is in mg per cat, not mg/kg. Higher dose should be carefully used in FeLV-infected cats because side effects, particularly non-regenerative anemia, can develop.
- FeLV: If giving SC, dilute in sterile normal saline to prevent local irritation. Check CBC weekly the first month.
Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.
Resumen
La zidovudina (AZT) es un inhibidor de la transcriptasa inversa análogo de nucleósido (ITIAN) utilizado principalmente en medicina veterinaria como tratamiento coadyuvante para el virus de la inmunodeficiencia felina (VIF) y el virus de la leucemia felina (ViLeF).
- Utilidad clínica: Aunque puede reducir la carga viral en gatos infectados y mejorar los signos clínicos (como la estomatitis o las manifestaciones neurológicas), no es una cura y puede no alterar significativamente el curso natural de la enfermedad a largo plazo.
- Perla clínica: Debido a que los retrovirus se integran en el genoma del huésped, los ITIAN como la zidovudina son más eficaces para prevenir la infección de nuevas células que para eliminar las células ya infectadas.
Mecanismo de acción
Zidovudine is a synthetic thymidine analogue.
- Mechanism: It is converted in vivo by cellular kinases into its active metabolite, zidovudine triphosphate.
- Pathway: Zidovudine triphosphate competes with natural thymidine triphosphate for incorporation into viral DNA by viral RNA-directed DNA polymerase (→ reverse transcriptase).
- Effect: Because zidovudine lacks a 3'-OH group, its incorporation prevents the formation of phosphodiester linkages, leading to DNA chain termination and a virustatic effect against retroviruses.
- It also possesses some activity against gram-negative bacteria and can exhibit host cell cytotoxicity (particularly in rapidly dividing cells like bone marrow).
Seguridad y advertencias
Contraindicaciones
- Patients with a history of life-threatening hypersensitivity reactions to zidovudine
Efectos adversos
- Non-regenerative anemia (most common in cats, dose-dependent)
- Reductions in RBCs, PCV, and hemoglobin
- Diarrhea
- Weakness
- Granulocytopenia (reported in humans)
- Gastrointestinal effects
Precauciones
Bone Marrow Suppression: Use with extreme caution in patients with pre-existing bone marrow dysfunction. Cats with bone marrow suppression should generally not be treated with zidovudine.
- Organ Dysfunction: Dosage adjustment may be necessary in cats with renal or hepatic dysfunction.
- Pregnancy: FDA Category C for use during pregnancy (animal studies show adverse fetal effects, but adequate human studies are lacking).
- Lactation: Excreted in milk; clinical significance for nursing offspring is unclear.
Interacciones farmacológicas
May increase zidovudine levels
May increase zidovudine levels
May antagonize each other's effects; avoid concurrent use. Also increases risk of hematologic toxicity.
Increased risk for hematologic and hepatotoxicity
May increase zidovudine levels
Administered with zidovudine may increase the risk of hematologic toxicity
May decrease blood levels (AUC) of zidovudine
Monitorización
- CBC (Complete Blood Count): Weekly for the first month of treatment (non-regenerative anemia is common, especially at higher doses). If stable, monthly checks are sufficient.
- Hematocrit: If PCV drops below 20%, treatment should be discontinued (anemia usually resolves within a few days).
- CD4/CD8 ratios (if possible)
- Clinical efficacy and improvement of signs
Farmacocinética
Vida media
Absorción
Well absorbed after oral administration. In cats, oral bioavailability is approximately 95%. When administered with food, peak levels may be decreased, but total AUC is generally unaffected. Peak levels occur about 1 hour post-dosing in cats.
Distribución
Widely distributed throughout the body, including penetration into the cerebrospinal fluid (CSF). It is only marginally bound to plasma proteins.
Metabolismo
Rapidly metabolized in vivo.
Eliminación
Excreted primarily in the urine.
Sobredosis
Human adults and children have survived massive oral overdoses (up to 50 grams) without permanent sequelae.
- Clinical Signs: Vomiting and transient hematologic effects (e.g., bone marrow suppression) are the most consistent adverse effects reported with acute overdoses.
- Management: Treatment is largely supportive and symptomatic, focusing on gastrointestinal decontamination if caught early, and monitoring hematologic parameters.
Productos disponibles
Formulaciones
- Tablets
- Capsules
- Syrup
- Injection solution
Etiquetado para humanos
- Zidovudine Oral Tablets: 300 mg (Retrovir, generic)
- Zidovudine Oral Capsules: 100 mg (Retrovir, generic)
- Zidovudine Oral Syrup: 50 mg/5 mL in 240 mL (Retrovir, generic)
- Zidovudine Injection Solution: 10 mg/mL in 20 mL single-use vials (Retrovir)
Estado regulador
Sin datos reguladores para: 🇺🇸 US · 🇪🇺 EU · 🇬🇧 UK · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Almacenamiento y estabilidad
Oral tablets, capsules, and syrup should be stored at room temperature. Protect from heat, light, and moisture. Injection (for IV infusion) should be stored at room temperature and protected from light.
Información para el cliente
- Terapia experimental: Este medicamento se considera una terapia 'experimental' o fuera de etiqueta para gatos con infecciones virales.
- Cumplimiento estricto: Debe administrarse exactamente como lo prescribió su veterinario para mantener la eficacia contra el virus.
- Análisis de sangre obligatorios: Es absolutamente necesario realizar visitas veterinarias periódicas para análisis de sangre (a menudo semanalmente al principio), ya que este fármaco puede causar anemia grave.
- Vigile los efectos secundarios: Comuníquese con su veterinario de inmediato si su gato se muestra inusualmente débil, letárgico, presenta encías pálidas o deja de comer.
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.