Butorphanol

What is this medication for?

• Chronic non-productive cough (tracheobronchitis etc.)
• Pre-anesthetic, mild-moderate analgesia, antiemetic (pre-cisplatin)
• Colic-associated pain
• Sedation/analgesia combos, chemical restraint

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.

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

• Transient wobbliness/unsteadiness/drowsiness; CNS excitement at high into a vein doses (Dose-related)

Worth a phone call to your veterinarian

• Sedation, wobbliness/unsteadiness, loss of appetite/diarrhea (Occasional, rarely severe)

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

• Trouble breathing, collapse, seizures, severe vomiting or diarrhea, facial swelling, or pale gums

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

• has or has had: Hypersensitivity
• has or has had: Liver disease (manufacturer specific warning); lower-respiratory conditions with copious mucus (antitussive suppresses productive cough); MDR1-mutant dogs — reduce dose 25% (het) to 30–50% (homozygous); heartworm disease (safety not established)

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Other CNS depressants
  • Erythromycin, theophylline
  • Fentanyl/other pure agonists

Storage and handling

Store at room temperature unless your prescription label says otherwise. Keep all medications out of reach of children and pets.

Good to know

• Poor choice as sole analgesic for moderate–severe small-animal pain — short analgesic duration (~1h) despite longer drowsiness.
• Available in two injectable strengths (0.5 mg/mL and 10 mg/mL) — inadvertent 20x overdose risk if concentration is confused.
• Reduce dose in MDR1-mutant breeds (Collies, Australian Shepherds, etc.) — more pronounced/prolonged drowsiness.