Cefaclor for Cats

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

Cefaclor is dosed at 10–15 mg/kg PO q8h in cats, per Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.225 (2026-08-01). — Plumb's 10th ed (held) printed p.197, Cefaclor monograph; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207. Cefaclor is used in cats for Urinary tract infection. Routes documented in cats: PO. A typical adult cat weighs 2.50–7.00 kg. ExoticRx lists 1 cited dose rule for Cefaclor in cats, drawn from published veterinary references. Verify against current literature before clinical use.

US trade names: Ceclor, Raniclor

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
PO	10–15 mg/kg	q8h	10-14 days	Urinary tract infection	Weak	Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.225 (2026-08-01). — Plumb's 10th ed (held) printed p.197, Cefaclor monograph; page located 2026-08-05 from the book's own running heads, verified to name the drug in its body text. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207

What each reference text prints

Every held source for this drug and species, as printed. Where they differ, both are shown — the choice is yours, not ours.

Printed doses in mg/kg for this drug and species, by source
Dose (mg/kg)	Route	Source	As printed
15–20	PO	Papich Saunders Handbook of Veterinary Drugs, 4th edp.144	• 15-20 mg/kg q8h PO. • 15-20 mg/kg q8h PO.

Figures are transcribed from the cited page or table of each held edition and are shown for reference only. They are not dose recommendations, they do not feed the calculator, and none has been reviewed by a veterinarian.

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Mechanism of action

Binds to penicillin-binding proteins (PBPs) and inhibits bacterial cell wall synthesis. Bactericidal.

Side effects & warnings

GI upset possible. Cross-reactivity with penicillin allergy. Adjust dose in renal impairment.

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 Cefaclor for Cats?

Cefaclor dose range in cats, with cited source references: PO 10–15 mg/kg q8h. Reference ranges from cited sources — verify against current literature before clinical use.

How is Cefaclor administered in Cats?

Documented routes for Cefaclor in cats: PO.

How long is Cefaclor given in Cats?

Cited course lengths for Cefaclor in cats include: 10-14 days. Duration depends on the indication — match it to the specific dose rule in the table above.

What conditions does Cefaclor treat in Cats?

Cefaclor is indicated in cats for: Urinary tract infection.

What are the side effects of Cefaclor in Cats?

These are general warnings for Cefaclor across species; consult the cat dosing table above for species-specific guidance. GI upset possible. Cross-reactivity with penicillin allergy. Adjust dose in renal impairment.

Other Antibiotic drugs with cat dosing

Amikacin Amoxicillin Amoxicillin Injectable Amoxicillin-Clavulanate Ampicillin Azithromycin Bacitracin Carbenicillin Cefadroxil Cefazolin Cefdinir Cefepime

Cefaclor dosing in other species

Dogs

See all species for Cefaclor See all drugs for Cats

Why a species-specific page? Cefaclor 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.