Sulfasalazine
Also known as: Azulfidine, Azulfidine EN-tabs, Salazopyrin
> **CRITICAL WARNING**: This medication can cause "dry eye" (Keratoconjunctivitis sicca) in dogs, which can lead to permanent blindness if ignored. - **Monitor your pet's eyes closely**. Contact your veterinarian immediately if you notice squinting, redness, thick yellow/green eye discharge, or if the eyes appear dull and dry. - **Administration**: Give with food to reduce stomach upset. If using enteric-coated tablets, do not crush or break them. - **Cats**: Cats are highly sensitive to this medication. Follow your veterinarian's exact dosing instructions and do not exceed the prescribed duration. - **Side Effects**: Watch for loss of appetite, vomiting, or yellowing of the gums/eyes (jaundice).
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
What it is used for
- Inflammatory large bowel disease
- Inflammatory large bowel disease
- Inflammatory large bowel disease
- Inflammatory large bowel disease
- All uses (Management of colitis)
- General
- General
- Inflammatory large bowel disease
- Inflammatory large bowel disease
- Chronic colitis
- Inflammatory large bowel disease
- Adjunctive treatment of vasculitis
- Adjunctive treatment of vasculitis
- All uses (Management of colitis)
How it is given
Possible side effects
- Keratoconjunctivitis sicca (KCS) in dogs
- Anorexia
- Vomiting
- Cholestatic jaundice
- Hemolytic anemia
- Leukopenia
- Decreased sperm counts
- Allergic dermatitis
- Keratoconjunctivitis sicca (KCS)
Cautions & contraindications
- Hypersensitivity to sulfasalazine, sulfonamides, or salicylates
- Intestinal or urinary obstructions
- Doberman pinschers (highly susceptible to sulfonamide-induced polysystemic immune complex disease)
- Dobermanns (appear to be highly sensitive to adverse effects associated with sulfapyridine)
- Patients with known hypersensitivity to sulfonamides or salicylates
- Use with caution in animals with preexisting **liver, renal, or hematologic diseases**. > **Feline Warning**: Because cats have a deficient glucuronidation pathway, they are highly sensitive to salicylates. Use extreme caution and strict dosing when using this drug in cats. Use with caution in nursing patients, as sulfonamides are excreted in milk and may cause kernicterus in newborns.
Drug interactions
- Chlorpropamide: Hypoglycemic effects could be potentiated
- Digoxin: Sulfasalazine may reduce absorption of digoxin
- Ferrous sulfate (or other iron salts): May decrease the blood levels of sulfasalazine if administered concurrently
- Folic acid: Oral absorption of folic acid may be inhibited
- Warfarin: Potentially sulfasalazine could potentiate warfarin
- Folate: Measurement of serum folate concentration may be affected
- Thyroxine: May cause a reduction in serum thyroxine concentrations
Frequently asked questions
What is Sulfasalazine used for in pets?
> **CRITICAL WARNING**: This medication can cause "dry eye" (Keratoconjunctivitis sicca) in dogs, which can lead to permanent blindness if ignored. - **Monitor your pet's eyes closely**. Contact your veterinarian immediately if you notice squinting, redness, thick yellow/green eye discharge, or if the eyes appear dull and dry. - **Administration**: Give with food to reduce stomach upset. If using enteric-coated tablets, do not crush or break them. - **Cats**: Cats are highly sensitive to this medication. Follow your veterinarian's exact dosing instructions and do not exceed the prescribed duration. - **Side Effects**: Watch for loss of appetite, vomiting, or yellowing of the gums/eyes (jaundice).
Is Sulfasalazine safe for my pet?
Dosage must be set by your veterinarian for your specific pet. Never give human medication or another pet’s prescription without veterinary guidance.
This article is for general education and is not a substitute for professional veterinary advice. If your pet is unwell, please consult a veterinarian.
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