Cat · Felis catus · typical adult weight 2.50–7.00 kg
Sulfasalazine is dosed at 10–20 mg/kg PO q12-24h in cats, per Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.1230 (2026-08-01). — Plumb's 10th ed (held) printed p.1203, Sulfasalazine monograph spanning p.1202-1203; page located 2026-08-05 from the book's own running heads, and carries this exact dose under the matching species heading. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207. Sulfasalazine is used in cats for Inflammatory bowel disease / colitis, Colitis. Routes documented in cats: PO. A typical adult cat weighs 2.50–7.00 kg. ExoticRx lists 2 cited dose rules for Sulfasalazine in cats, drawn from published veterinary references. Verify against current literature before clinical use.
US trade names: Azulfidine
| Route | Dose | Frequency | Duration | Indication | Evidence | Source |
|---|---|---|---|---|---|---|
| PO | 10–20 mg/kg | q12-24h | 2-4 weeks, then reassess | Inflammatory bowel disease / colitis | Moderate | Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.1230 (2026-08-01). — Plumb's 10th ed (held) printed p.1203, Sulfasalazine monograph spanning p.1202-1203; page located 2026-08-05 from the book's own running heads, and carries this exact dose under the matching species heading. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 |
| PO | 10–20 mg/kg | q12h | 4-6 weeks | Colitis | Weak | Verified against Plumb's Veterinary Drug Handbook, 10th Ed, p.1230 (2026-08-01). — Plumb's 10th ed (held) printed p.1203, Sulfasalazine monograph spanning p.1202-1203; page located 2026-08-05 from the book's own running heads, and carries this exact dose under the matching species heading. — SOURCE EDITION: Plumb's Veterinary Drug Handbook — ISBN 9781394172207, https://openlibrary.org/isbn/9781394172207 |
Every held source for this drug and species, as printed. Where they differ, both are shown — the choice is yours, not ours.
| Dose (mg/kg) | Route | Source | As printed |
|---|---|---|---|
| 10–20 | PO | BSAVA Small Animal Formulary, 10th ed — Part A (Canine and Feline)p.404 | 10-20 mg/kg p.o. q8-12h. Sulphonamide see Trimethoprim/ sulphonamide BSAVA Small Ani |
| 20 | PO | Papich Saunders Handbook of Veterinary Drugs, 4th edp.784 | • 20 mg/kg q12h 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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Cleaved by colonic bacteria to 5-aminosalicylic acid (mesalamine) and sulfapyridine. 5-ASA acts locally to reduce colonic inflammation.
Used for colitis in dogs. KCS (dry eye) risk — monitor Schirmer tear test. Cats: salicylate sensitivity. Folate supplementation recommended. GI upset.
Species-specific contraindications and adverse-reaction reports for cats may differ from canine / feline reference data — consult the primary citations listed with each rule.
Sulfasalazine dose ranges in cats, with cited source references: PO 10–20 mg/kg q12-24h; PO 10–20 mg/kg q12h. Reference ranges from cited sources — verify against current literature before clinical use.
Documented routes for Sulfasalazine in cats: PO.
Cited course lengths for Sulfasalazine in cats include: 2-4 weeks, then reassess; 4-6 weeks. Duration depends on the indication — match it to the specific dose rule in the table above.
Sulfasalazine is indicated in cats for: Inflammatory bowel disease / colitis, Colitis.
These are general warnings for Sulfasalazine across species; consult the cat dosing table above for species-specific guidance. Used for colitis in dogs. KCS (dry eye) risk — monitor Schirmer tear test. Cats: salicylate sensitivity. Folate supplementation recommended. GI upset.
Why a species-specific page? Sulfasalazine 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.