Enrofloxacin

What is this medication for?

• Susceptible bacterial infections (gram-negative predominant) — skin, UTI, respiratory

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.

• Never exceed 5 mg/kg/day in cats — this is a hard, well-documented ceiling to prevent irreversible retinal blindness.

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

• Cartilage/articular damage (Young, rapidly growing dogs (esp. large/giant breeds) — bubble-like cartilage lesions)
• stomach/intestinal distress, CNS stimulation, crystalluria (Occasional)

Worth a phone call to your veterinarian

• Any new symptom that worries you.

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

• Retinal degeneration/blindness (Dose-related, seen at >15–20 mg/kg — can be irreversible)

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

• has or has had: Small/medium breed dogs 2–8 months old (label); food-producing animals (extra-label use prohibited); do not exceed 5 mg/kg/day in cats
• has or has had: Seizure disorders (CNS stimulation risk); hepatic/renal impairment; dehydration (crystalluria risk)

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Antacids/dairy (cations)
  • Theophylline
  • Cyclosporine
  • NSAIDs (flunixin specifically studied)
  • Sucralfate
  • Nitrofurantoin

Storage and handling

Room temperature, protect from light. Do not mix with magnesium-containing into a vein solutions (e.g., Normosol-R) — precipitation risk reported to cause pulmonary microembolism/death.

Good to know

• Never exceed 5 mg/kg/day in cats — this is a hard, well-documented ceiling to prevent irreversible retinal blindness.
• Avoid in growing dogs (2–8 months for small/medium breeds; larger breeds need longer windows since growth continues past 8 months) — cartilage damage risk.
• The injectable large-animal product (100 mg/mL) should not be diluted/used in small animals — reserve the correctly concentrated small-animal product.
• Should not be used by humans handling it — can cause hallucinations/vivid dreams/headache.