Tylosin

What is this medication for?

• Chronic enteropathy / antibiotic-responsive diarrhea (ARD); tylosin-responsive diarrhea; tear staining (epiphora, extra-label cosmetic)
• IBD adjunct; Clostridium perfringens colitis; anecdotal immunomodulator in FIP

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

• Tylosin-responsive diarrhea is a real, relapsing phenotype: stool normalizes while on treatment and diarrhea returns within weeks of stopping (Kilpenn) — owners of responders often need long-term pulse or continuous low-dose therapy.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• stomach/intestinal upset (loss of appetite, diarrhea) (Main oral effect)

Worth a phone call to your veterinarian

• Pain/local reaction at into a muscle injection sites (Injectable use (rare parenteral use in small animals))

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Fatal colitis (Horses — contraindicated (species note))

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Macrolide hypersensitivity; horses (severe/fatal diarrhea)
• has or has had: Oral ruminant use causes severe diarrhea (species note)

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Digoxin
  • Erythromycin-class interactions

Storage and handling

Powder/store room temperature. Tylan Soluble powder 100 g bottles; bitter — encapsulate for cats.

Good to know

• Tylosin-responsive diarrhea is a real, relapsing phenotype: stool normalizes while on treatment and diarrhea returns within weeks of stopping (Kilpenn) — owners of responders often need long-term pulse or continuous low-dose therapy.
• Bacteriostatic 50S binder like erythromycin — but at canine/feline doses its clinical niche is chronic enteropathy, not systemic infection.
• May also act immunomodulatorily and increase jejunal probiotic enterococci — rationale beyond pure antibiosis.
• Safety margin is wide (2-year 400 mg/kg/day oral studies in dogs without organ toxicity).