Amoxicillin Injectable for Cats

Cat · Felis catus · typical adult weight 2.50–7.00 kg

Amoxicillin Injectable is dosed at 10–20 mg/kg SC q12h in cats, per Plumb's Veterinary Drug Handbook, 9th Ed. Amoxicillin Injectable is used in cats for Bacterial infections. Routes documented in cats: SC. A typical adult cat weighs 2.50–7.00 kg. ExoticRx lists 1 cited dose rule for Amoxicillin Injectable in cats, drawn from published veterinary references. Verify against current literature before clinical use.

US trade names: Amoxi-Inject

Contraindicated in Rabbit, Guinea Pig, Chinchilla, Hamster, Degu

Rabbit: Oral beta-lactams cause fatal dysbiosis in rabbitsOral amoxicillin (and other oral beta-lactams) selectively destroy gram-positive hindgut flora in rabbits, allowing Clostridium spiroforme overgrowth and fatal enterotoxemia. Never administer oral beta-lactams to rabbits. Parenteral administration carries a lower risk than the oral route, but is not established as safe in rabbits.
Guinea Pig: Oral beta-lactams cause fatal dysbiosis in guinea pigsOral amoxicillin reliably causes Clostridium difficile-mediated fatal enterotoxemia in guinea pigs. Same mechanism as in rabbits. Parenteral administration carries a lower risk than the oral route; parenteral ceftiofur specifically has been given to guinea pigs and chinchillas without adverse effect.
Chinchilla: Oral beta-lactams cause fatal dysbiosis in chinchillasChinchillas are hindgut fermenters with the same flora dependence as rabbits and guinea pigs. Oral penicillins and oral cephalosporins trigger Clostridium overgrowth and fatal enterotoxemia. Never give oral beta-lactams; parenteral routes and trimethoprim-sulfa, fluoroquinolones, or chloramphenicol are the safer choices.

Hamster: Oral beta-lactams cause fatal enterocolitis in hamstersHamsters are exquisitely susceptible to antibiotic-associated Clostridium difficile enterocolitis — the hamster is the classic laboratory model for it. Oral penicillins and cephalosporins are reliably fatal. Never administer oral beta-lactams.

Degu: Oral beta-lactams risk fatal dysbiosis in degusDegus are caviomorph hindgut fermenters closely related to chinchillas and guinea pigs. Degu-specific data is limited, so this warning is extrapolated from those related hystricomorphs — but the shared physiology makes oral beta-lactam enterotoxemia the expected outcome. Treat as contraindicated; use the safer alternatives.

Dose ranges

Route	Dose	Frequency	Duration	Indication	Evidence	Source
SC	10–20 mg/kg	q12h	7-14 days	Bacterial infections	Moderate	Plumb's Veterinary Drug Handbook, 9th Ed

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Mechanism of action

Aminopenicillin inhibiting cell wall synthesis. Injectable form for patients unable to take oral medication.

Side effects & warnings

CONTRAINDICATED in rabbits, guinea pigs, hamsters. IM injection may be painful. Same spectrum as oral amoxicillin.

Species-specific contraindications and adverse-reaction reports for cats may differ from canine / feline reference data — consult the primary citations listed with each rule.

Frequently asked questions

What is the dose of Amoxicillin Injectable for Cats?

Amoxicillin Injectable dose range in cats, with cited source references: SC 10–20 mg/kg q12h. Reference ranges from cited sources — verify against current literature before clinical use.

How is Amoxicillin Injectable administered in Cats?

Documented routes for Amoxicillin Injectable in cats: SC.

How long is Amoxicillin Injectable given in Cats?

Cited course lengths for Amoxicillin Injectable in cats include: 7-14 days. Duration depends on the indication — match it to the specific dose rule in the table above.

What conditions does Amoxicillin Injectable treat in Cats?

Amoxicillin Injectable is indicated in cats for: Bacterial infections.

What are the side effects of Amoxicillin Injectable in Cats?

These are general warnings for Amoxicillin Injectable across species; consult the cat dosing table above for species-specific guidance. CONTRAINDICATED in rabbits, guinea pigs, hamsters. IM injection may be painful. Same spectrum as oral amoxicillin.

Why a species-specific page? Amoxicillin Injectable pharmacokinetics differ across species: dose ranges, intervals, and route preferences are not interchangeable. Cross-extrapolation from canine doses is unsafe in cats — the rules above are the citations specific to this species, not generic recommendations.

Sourced from published veterinary references; awaiting credentialed clinical reviewer. See our editorial process. Reference only — not veterinary advice.