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.
Sourced from published veterinary references. Awaiting credentialed clinical reviewer — our editorial process.
Oxacillin is dosed at 22–40 mg/kg IV q8h in dogs, per Plumb's Veterinary Drug Handbook, 9th ed, printed p.964 (corpus pdf p.991), Oxacillin, DOGS/CATS: 'Susceptible infections (extra-label): 22 - 40 mg/kg SC, IM, or IV every 8 hours'. Corroborated by Papich, Saunders Handbook of Veterinary Drugs, 5th ed, printed p.586 (corpus pdf p.614), Oxacillin, Dogs and Cats: '22-40 mg/kg q8h PO.'. Verify against current literature before clinical use.
Each ExoticRx dose rule is graded by the strength of its primary evidence — see the editorial process.
Backed by a published source
· Plumb's Veterinary Drug Handbook, 9th ed, printed p.964 (corpus pdf p.991), Oxacillin, DOGS/CATS: 'Susceptible infections (extra-label): 22 - 40 mg/kg SC, IM, or IV every 8 hours'. Corroborated by Papich, Saunders Handbook of Veterinary Drugs, 5th ed, printed p.586 (corpus pdf p.614), Oxacillin, Dogs and Cats: '22-40 mg/kg q8h PO.'
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