Vet Guide to Buprenorphine in 2025 🐾

Hi, I’m Dr Duncan Houston, BVSc—founder of Ask A Vet. In this comprehensive 2025 guide, we explore buprenorphine: a Schedule III opioid used safely for mild to moderate pain relief in dogs and cats. Whether delivered as Buprenex®, Simbadol®, or Zorbium®, we'll cover how it works, dosing, safety, side effects, storage, and best monitoring practices. 🩺

📘 What Is Buprenorphine?

Buprenorphine is a partial μ-opioid receptor agonist that provides effective analgesia with a ceiling effect, minimizing severe respiratory depression. It’s commonly used perioperatively or for postoperative and acute pain control in small animals. It’s available under several formulations:

• Buprenex®: Injectable human-labeled form used off-label for pets :contentReference[oaicite:3]{index=3}.
• Simbadol®: FDA-approved, single daily high-dose injectable for cats (0.24 mg/kg SC) lasting ~24 hrs :contentReference[oaicite:4]{index=4}.
• Zorbium®: FDA-approved transdermal gel delivering 4 days of analgesia in cats :contentReference[oaicite:5]{index=5}.

🔬 How It Works

By partial activation of μ-opioid receptors, buprenorphine provides analgesia with reduced risk of adverse respiratory effects. It has a ceiling effect—beyond a certain dose, increasing amounts don’t intensify the effect, just duration :contentReference[oaicite:6]{index=6}.

📐 Dosing & Administration

🐶 Dogs

• Injectable Buprenex®: Typically every 6–12 hrs in hospital; can be prescribed for at-home transmucosal use; duration depends on dose :contentReference[oaicite:7]{index=7}.
• Transmucosal (oral gel): Administered onto gums, absorbed via oral mucosa for home pain relief :contentReference[oaicite:8]{index=8}.

🐱 Cats

• Simbadol®: 0.24 mg/kg SC once daily for up to 3 days is official label use :contentReference[oaicite:9]{index=9}.
• Zorbium®: Single in-clinic topical dose provides 4 days coverage. Dose by weight: 8 mg for cats 2.6–6.6 lb; 20 mg for >6.6–16.5 lb :contentReference[oaicite:10]{index=10}.
• Transmucosal/oral: Often used every 8–12 hrs for at-home pain control :contentReference[oaicite:11]{index=11}.

⏱️ Onset & Duration

• Onset: ~30–45 minutes transmucosally; injectable forms act faster :contentReference[oaicite:12]{index=12}.
• Duration: Buprenex® lasts 6–12 hrs; Simbadol provides ~24 hrs; Zorbium lasts ~4 days :contentReference[oaicite:13]{index=13}.

⚠️ Side Effects & Safety

Common:

• Sedation/drowsiness (≈66%) :contentReference[oaicite:14]{index=14}.
• GI: nausea, vomiting, drooling, constipation, reduced appetite :contentReference[oaicite:15]{index=15}.
• Behavioral changes: during recovery, agitation or increased vocalization possible :contentReference[oaicite:16]{index=16}.

Less common/serious:

• Respiratory depression—rare in normal patients :contentReference[oaicite:17]{index=17}.
• Slow heart rate, low body temperature :contentReference[oaicite:18]{index=18}.
• Hyperthermia or agitation, especially in cats :contentReference[oaicite:19]{index=19}.

🩺 Who Needs Monitoring?

• Observe sedation, breathing, heart rate after administration.
• Be ultra-cautious in pets with respiratory, cardiac, hepatic, renal, or CNS disease :contentReference[oaicite:20]{index=20}.
• Record and secure dosage—buprenorphine is a controlled substance with abuse potential :contentReference[oaicite:21]{index=21}.

🔗 Interactions & Contraindications

• Don't use with other opioids unless under vet guidance due to additive effects :contentReference[oaicite:22]{index=22}.
• Drug interactions: azole antifungals, erythromycin, sedatives, phenobarbital, CNS depressants, MAO inhibitors like selegiline :contentReference[oaicite:23]{index=23}.
• Avoid in pregnant/lactating pets; crosses placenta and into milk :contentReference[oaicite:24]{index=24}.

🚨 Missed Dose & Overdose

• Missed dose? Administer when remembered and maintain schedule—never double-dose :contentReference[oaicite:25]{index=25}.
• Overdose signs: increased sedation, low temperature, slow breathing, ataxia—call vet or poison helpline :contentReference[oaicite:26]{index=26}.

🧊 Storage & Handling

• Store at room temperature (68–77 °F), protected from light :contentReference[oaicite:27]{index=27}.
• Zorbium® requires gloves, PPE, and drying time; no contact for 30 min post-application :contentReference[oaicite:28]{index=28}.
• Secure storage required—controlled substance regulations apply :contentReference[oaicite:29]{index=29}.

🏡 Case Examples

🐶 Post-op Dog

• Hospital: injectable Buprenex® every 8 hrs for 24 hrs.
• At home: transmucosal gel BID for 48–72 hrs; monitor food & behavior.

🐱 Surgical Cat

• Administer Simbadol® 0.24 mg/kg SC 1 hr before discharge; monitor sedation & appetite.
• For multi-day care, consider Zorbium® in-clinic for 4-day relief.

❓ FAQs

Is buprenorphine safe at home?

Yes, with proper dosing instructions—transmucosal routes are effective for gentle home pain management :contentReference[oaicite:30]{index=30}.

What’s the difference between Simbadol® and Zorbium®?

Simbadol® is a 24‑hour injectable; Zorbium® is a 4‑day topical gel—both FDA-approved for post-op feline pain :contentReference[oaicite:31]{index=31}.

📌 Final Takeaways

• Buprenorphine is a safe, partial opioid for mild-to-moderate pain in dogs and cats.
• Modes include injection, transmucosal gel, high-dose injectable (cats), and 4-day topical (Zorbium®).
• Provides sedation and analgesia with low risk at appropriate doses; secure storage required.
• Monitor especially at treatment start and in high-risk patients; never double-dose.
• If adverse effects occur, contact a veterinarian promptly; reversal agents exist (e.g., naloxone).

Interested in using buprenorphine safely for your pet’s pain? Download the Ask A Vet app for expert dosing help, monitoring tools & 24/7 veterinary support. Your pet’s comfort is our priority! 🐾❤️