Amoxicilina
Amoxicillin
Amoxicillin trihydrate
También conocido como: Amoxil · Amoxi-Tabs · Amoxi-Drop · Amoxi-Mast · Trimox · Moxatag · Amoxibactin · Amoxycare · Amoxypen · Betamox · Bimoxyl · Clamoxyl · amoxycillin · p-hydroxyampicillin · BRL 2333
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 |
|---|---|---|---|---|---|
| Gram-positive infections | 10 mg/kg PO, IM, SC twice daily for at least 2 days after symptoms subside. | PO, IM, SC | q12h | At least 2 days after symptoms subside | 🌎 NA |
| Gram-negative infections | 20 mg/kg PO three times daily or IM, SC twice daily for at least 2 days after symptoms subside | PO, IM, SC | q8h (PO) or q12h (IM, SC) | At least 2 days after symptoms subside | 🌎 NA |
| Susceptible UTI's | 10-20 mg/kg PO q12h for 5-7 days. | PO | q12h | 5-7 days | 🌎 NA |
| Susceptible systemic infections (bacteremia/sepsis) | 22-30 mg/kg IV , IM, SC q8h for 7 days. | IV, IM, SC | q8h | 7 days | 🌎 NA |
| Susceptible orthopedic infections | 22-30 mg/kg IV , IM, SC, or PO q6-8h for 7-10 days. | IV, IM, SC, PO | q6-8h | 7-10 days | 🌎 NA |
| Lyme disease | 22 mg/kg PO q12h for 21-28 days | PO | q12h | 21-28 days | 🌎 NA |
| Susceptible urinary tract infections | 11 mg/kg PO q8h. | PO | q8h | — | 🌎 NA |
| Preventative therapy for repeated (>2 per 6 months) urinary tract Gram-positive bacterial infections | 20 mg/kg PO once daily before bedtime after the dog has urinated. | PO | q24h | — | 🌎 NA |
| Susceptible bacterial infections | 7 mg/kg | IM | q24h | — | 🌍 EU |
| Susceptible bacterial infections (depot preparations) | 15 mg/kg | IM | q48h | — | 🌍 EU |
| Susceptible bacterial infections | 10 mg/kg | PO | q8-12h | — | 🌍 EU |
| Bacterial cystitis | 11-15 mg/kg | PO | q8h | — | 🌍 EU |
- Preventative therapy for repeated (>2 per 6 months) urinary tract Gram-positive bacterial infections: Use only after effective treatment completed using full therapeutic doses.
- Susceptible bacterial infections (depot preparations): For depot preparations only
- Susceptible bacterial infections: Dose chosen will depend on site of infection, causal organism and severity of the disease.
- Bacterial cystitis: Evidence of a need for clavulanic acid is lacking even in infections with beta-lactamase producing bacteria.
Gatos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Gram-positive infections | 10 mg/kg PO, IM, SC twice daily for at least 2 days after symptoms subside. | PO, IM, SC | q12h | At least 2 days after symptoms subside | 🌎 NA |
| Gram-negative infections | 20 mg/kg PO three times daily or IM, SC twice daily for at least 2 days after symptoms subside | PO, IM, SC | q8h (PO) or q12h (IM, SC) | At least 2 days after symptoms subside | 🌎 NA |
| Susceptible UTI's and soft tissue infections | 50 mg (total dose per cat) or 11-22 mg/kg PO once daily for 5-7 days. | PO | q24h | 5-7 days | 🌎 NA |
| Sepsis | 10-20 mg/kg IV , SC, or PO q12h for as long as necessary. | IV, SC, PO | q12h | As long as necessary | 🌎 NA |
| C. perfringens, bacterial overgrowth (GI) | 22 mg/kg PO once daily for 5 days | PO | q24h | 5 days | 🌎 NA |
| C. perfringens enterotoxicosis | 11-22 mg/kg PO two to three times daily for 7 days | PO | q8-12h | 7 days | 🌎 NA |
| H. pylori infections (triple therapy) | amoxicillin 20 mg/kg PO twice daily for 14 days; metronidazole 10-15 mg/kg PO twice daily; clarithromycin 7.5 mg/kg PO twice daily | PO | q12h | 14 days | 🌎 NA |
| Susceptible bacterial infections | 7 mg/kg | IM | q24h | — | 🌍 EU |
| Susceptible bacterial infections (depot preparations) | 15 mg/kg | IM | q48h | — | 🌍 EU |
| Susceptible bacterial infections | 10 mg/kg | PO | q8-12h | — | 🌍 EU |
| Bacterial cystitis | 11-15 mg/kg | PO | q8h | — | 🌍 EU |
- Sepsis: Generally treat for at least 2 days after all signs of infection are gone.
- H. pylori infections (triple therapy): Used in combination with metronidazole and clarithromycin.
- Susceptible bacterial infections (depot preparations): For depot preparations only
- Susceptible bacterial infections: Dose chosen will depend on site of infection, causal organism and severity of the disease.
- Bacterial cystitis: Evidence of a need for clavulanic acid is lacking even in infections with beta-lactamase producing bacteria.
Pequeños mamíferos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Susceptible infections (Hedgehogs) | 15 mg/kg IM or PO q12h | IM, PO | q12h | — | 🌎 NA |
- Susceptible infections (Hedgehogs): See contraindications regarding use in rabbits/rodents.
Hurones
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Eliminating Helicobacter gastritis infections (triple therapy) | Metronidazole 22 mg/kg, amoxicillin 22 mg/kg and bismuth subsalicylate (original Pepto-Bismol ®) 17.6 mg/kg PO. Give each 3 times daily for 3-4 weeks. | PO | q8h | 3-4 weeks | 🌎 NA |
| Eliminating Helicobacter gastritis infections (triple therapy) | Metronidazole 20 mg/kg PO q12h, amoxicillin 20 mg/kg PO q12h and bismuth subsalicylate 17.5 mg/kg PO q8h. Give 21 days. | PO | q12h | 21 days | 🌎 NA |
| Susceptible infections | 10-35 mg/kg PO or SC twice daily | PO, SC | q12h | — | 🌎 NA |
- Eliminating Helicobacter gastritis infections (triple therapy): Sucralfate and famotidine are also used. Fluids and assisted feeding should be continued.
Aves
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Susceptible infections | 125 mg/kg q12h PO. Mix oral solution to double strength to a final concentration of 125 mg/mL. | PO | q12h | — | 🌎 NA |
| Susceptible infections | 100 mg/kg q8h, IM, SC, PO | IM, SC, PO | q8h | — | 🌎 NA |
| Susceptible infections (Ratites) | 15-22 mg/kg PO twice daily; in drinking water: 250 mg/gallon for 3-5 days | PO, drinking water | q12h / continuous | 3-5 days | 🌎 NA |
Reptiles
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Susceptible infections (all species) | 22 mg/kg PO q12-24h | PO | q12-24h | — | 🌎 NA |
- Susceptible infections (all species): Not very useful unless used in combination with aminoglycosides
Caballos
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Respiratory infections | 20-30 mg/kg PO q6h | PO | q6h | — | 🌎 NA |
| Susceptible infections (Foals - Amoxicillin Sodium) | 15-30 mg/kg IV or IM q6-8h | IV, IM | q6-8h | — | 🌎 NA |
| Susceptible infections (Foals - Amoxicillin trihydrate suspension) | 25-40 mg/kg PO q8h | PO | q8h | — | 🌎 NA |
| Susceptible infections (Foals - Amoxicillin/clavulanate) | 15-25 mg/kg IV q6-8h | IV | q6-8h | — | 🌎 NA |
Ganado
| Indicación | Dosis | Vía | Frecuencia | Duración | Región |
|---|---|---|---|---|---|
| Susceptible infections | 6-10 mg/kg SC or IM q24h | SC, IM | q24h | — | 🌎 NA |
| Respiratory infections | 11 mg/kg IM or SC q12h | IM, SC | q12h | — | 🌎 NA |
| Susceptible infections (Calves - Amoxicillin trihydrate) | 7 mg/kg PO q8-12h | PO | q8-12h | — | 🌎 NA |
- Susceptible infections: Withdrawal time = 30 days
Las dosis son una referencia clínica para profesionales veterinarios autorizados. Confirme siempre con el prospecto actual y cada paciente individual.
Resumen
La amoxicilina es un antibiótico aminopenicilina de amplio espectro ampliamente prescrito en medicina veterinaria para tratar diversas infecciones bacterianas.
Las características farmacológicas clave incluyen:
- Espectro de actividad: Efectivo contra muchas bacterias Gram-positivas aerobias, algunas Gram-negativas aerobias (p. ej., E. coli, Klebsiella, Haemophilus) y muchas bacterias anaerobias obligadas (incluyendo Clostridium spp.).
- Susceptibilidad a las beta-lactamasas: Al igual que la ampicilina, es inactivada por bacterias productoras de beta-lactamasas (p. ej., Staphylococcus aureus). A menudo se combina con clavulanato para superar esta resistencia.
- Utilidad clínica: Se considera una elección empírica de primera línea para abscesos felinos, infecciones del tracto urinario (ITU) susceptibles e infecciones de tejidos blandos.
- Ventaja farmacocinética: En comparación con la ampicilina, la amoxicilina tiene una biodisponibilidad oral significativamente mejor en animales monogástricos, alcanzando niveles séricos de 1.5 a 3 veces mayores a dosis equivalentes.
Mecanismo de acción
Amoxicillin is a time-dependent, bactericidal antibiotic that disrupts bacterial cell wall synthesis.
- Mechanism: The beta-lactam ring mimics the D-alanyl-D-alanine terminal of the peptidoglycan precursor.
- Pathway: Amoxicillin binds to specific penicillin-binding proteins (PBPs) (such as transpeptidases, carboxypeptidases, and endopeptidases) located on the inner surface of the bacterial cell membrane → inhibits the cross-linking of mucopeptide (peptidoglycan) chains → compromises the structural integrity of the cell wall → creates an osmotically unstable spheroplast → results in cell lysis and death.
- Efficacy: It is most effective against actively dividing and growing bacteria.
Seguridad y advertencias
Contraindicaciones
- Patients with a history of hypersensitivity to penicillins
- Oral administration in hindgut fermenters (rabbits, guinea pigs, chinchillas, hamsters) due to risk of fatal clostridial enterotoxemia
- Oral administration in patients with septicemia, shock, or grave illness (due to delayed/diminished GI absorption)
Efectos adversos
- Gastrointestinal upset (anorexia, vomiting, diarrhea)
- Antibiotic-associated diarrhea and gut flora alteration
- Hypersensitivity reactions (rashes, fever, anaphylaxis)
- Eosinophilia, neutropenia, agranulocytosis, thrombocytopenia, leukopenia, anemias
- Lymphadenopathy
- Neurotoxicity (e.g., ataxia) at very high doses or prolonged use
- Elevated liver enzymes (rare)
- Tachypnea, dyspnea, edema, and tachycardia (reported in dogs)
Precauciones
Species Warning: Never administer amoxicillin (or other penicillins) orally to rabbits, guinea pigs, chinchillas, or hamsters, as it can cause severe, often fatal, clostridial enterotoxemia.
- Cross-Reactivity: Use with caution in patients with documented hypersensitivity to other beta-lactam antibiotics (e.g., cephalosporins, carbapenems).
- Pregnancy: Crosses the placenta. Categorized as FDA Category B (human) and Class A (veterinary - probably safe), but should be used only when potential benefits outweigh risks.
- Laboratory Tests: May cause false-positive urine glucose determinations when using cupric sulfate solutions (e.g., Clinitest).
Interacciones farmacológicas
Potential in vitro antagonism; concurrent use has historically been discouraged, though clinical significance is debated.
Amoxicillin may decrease the renal excretion of methotrexate, leading to increased levels and potential toxicity.
Competitively blocks the tubular secretion of penicillins, increasing serum levels and prolonging serum half-life.
In vitro inactivation of aminoglycosides by beta-lactams; may falsely decrease aminoglycoside serum concentrations if samples are stored prior to analysis.
Potential antagonism of bactericidal activity (bacteriostatic vs bactericidal)
Potential antagonism of bactericidal activity
Potential antagonism of bactericidal activity
Inactivation of aminoglycoside if mixed in the same syringe
Synergistic antimicrobial effect when used concurrently
Monitorización
- Clinical efficacy (resolution of infection signs)
- Adverse effects (GI upset, signs of hypersensitivity)
Farmacocinética
Vida media
Absorción
Relatively stable in gastric acid. About 74-92% absorbed orally in monogastric animals. Food decreases the rate but not the extent of absorption. Serum levels are generally 1.5-3 times greater than ampicillin after equivalent oral doses.
Distribución
Volume of distribution is ~0.2 L/kg in dogs. Widely distributed to tissues including liver, lungs, muscle, bile, and ascitic/pleural/synovial fluids. Crosses into CSF when meninges are inflamed (10-60% of serum levels). Crosses the placenta. Protein binding is ~13% in dogs.
Metabolismo
Some of the drug is metabolized by hydrolysis to inactive penicilloic acids.
Eliminación
Eliminated primarily through renal mechanisms, principally by tubular secretion. Clearance is reportedly 1.9 mL/kg/min in dogs.
Sobredosis
Acute oral penicillin overdoses are unlikely to cause significant problems other than gastrointestinal distress (vomiting, diarrhea, anorexia).
In humans, very high dosages of parenteral penicillins, especially in patients with compromised renal function, have induced CNS effects (e.g., seizures, ataxia). Treatment is generally supportive and symptomatic.
Productos disponibles
Formulaciones
- Oral tablets
- Oral chewable tablets
- Oral capsules
- Powder for oral suspension
- Intramammary infusion
Veterinario
- Amoxicillin Oral Tablets: 50 mg, 100 mg, 150 mg, 200 mg, & 400 mg (Amoxi-Tabs®)
- Amoxicillin Powder for Oral Suspension: 50 mg/mL after reconstitution (Amoxi-Drop®)
- Amoxicillin Intramammary Infusion: 62.5 mg/syringe (Amoxi-Mast®)
Etiquetado para humanos
- Amoxicillin Oral Tablets (chewable): 125 mg, 200 mg, 250 mg, & 400 mg (Amoxil®)
- Amoxicillin Oral Tablets: 500 mg & 875 mg (Amoxil®)
- Amoxicillin Oral Capsules: 250 mg & 500 mg (Amoxil®)
- Amoxicillin Powder for Oral Suspension: 200 mg/5 mL, 250 mg/5 mL, 400 mg/5 mL (Amoxil®, Trimox®)
- Amoxicillin Oral Extended-Release Tablets: 775 mg (Moxatag®)
Estado regulador
Sin datos reguladores para: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Almacenamiento y estabilidad
Capsules, tablets, and powder for oral suspension should be stored at room temperature (15-30°C) in tight containers. After reconstitution, the oral suspension should preferably be refrigerated (though not absolutely necessary) and any unused product discarded after 14 days.
Información para el cliente
- Administración: La amoxicilina puede administrarse con o sin comida. Sin embargo, si su mascota experimenta malestar estomacal (vómitos o pérdida de apetito), administrar el medicamento con una comida puede ayudar.
- Almacenamiento: Si está utilizando la suspensión oral líquida, es mejor mantenerla refrigerada, aunque la temperatura ambiente es aceptable. Deseche cualquier líquido no utilizado después de 14 días.
- Finalización del tratamiento: Siempre termine la receta completa según las indicaciones de su veterinario, incluso si su mascota parece estar completamente recuperada. Suspender el tratamiento antes de tiempo puede provocar infecciones bacterianas resistentes.
- Efectos secundarios: Puede ocurrir diarrea leve o vómitos. Si estos síntomas se vuelven graves, o si nota signos de una reacción alérgica (como hinchazón facial, urticaria o dificultad para respirar), comuníquese con su veterinario de inmediato.
- Advertencia sobre especies: Nunca comparta este medicamento con mascotas pequeñas como conejos, cobayas o hámsteres, ya que puede ser fatal para ellos.
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.