Dogs can overdose too: Naloxone training can save pets’ lives as well as humans

Administer naloxone right away if you suspect your dog is experiencing an opioid overdose. (Unsplash/Luke Macgillivray) Opioid-class drugs are commonly prescribed as powerful pain medications in both humans and animals, though they can also be accessed or used illicitly. These substances carry a significant risk of overdose in people and in pets because they slow the central nervous system. At high doses, this effect can slow the respiratory system to the point of stopping breathing. While any pet can experience opioid toxicity, dogs are particularly at risk because they rely heavily on their noses to explore their surroundings. This means they are more likely to directly inhale a substance through their nose, ingest it through their mouth or be exposed indirectly through contamination on their feet and fur. We know this as a veterinarian, a specialist in the human-animal bond and as trainers in opioid overdose response. The number of reported incidents of dogs ingesting opioids is low, because the risk of exposure is low and dogs possibly have a higher tolerance compared to humans. But when they do overdose, it is likely at a concerningly high dose. The most common illicit fentanyl exposure formulation in dogs reported to a North American Veterinary Poison Control Centre from 2019 to 2023 was powder/crystals (30 per cent). However, fear of reporting cases involving illicit opioids may result in under-reporting. Opioid crisis in Canada Approximately one in 10 Canadian households includes an individual prescribed an opioid. Over the past decade, Canada has seen a sharp rise in potent opioids such as fentanyl and carfentanyl in the unregulated drug market, leading to increased overdoses. From 2016-24, there were 53,821 reported apparent opioid toxicity deaths nationwide. These trends increase the likelihood that pets may gain access to opioids, putting them at risk of drug-related harms and potentially fatal overdose. Naloxone use in humans Naloxone is a safe and effective medication used to reverse the effects of an opioid overdose. In Canada, naloxone does not require a prescription and is available in two forms — intramuscular injection or nasal spray. Publicly funded Take Home Naloxone programs were launched nationwide from 2012 to 2017, providing naloxone kits to community members at no cost and without a prescription. Community-based training for Take Home Naloxone is available to everyone to support emergency response during an overdose. Naloxone kits contain standardized doses that are considered safe for human adults, children and infants. Administering naloxone will not cause harm if a person has not consumed opoids. Once trained, anyone can administer naloxone safely, and while naloxone can reverse the harms of an overdose within minutes, multiple doses may be required with more potent opioids. Different guidelines apply to first responders and when naloxone is used in clinical settings. In Canada, the Good Samaritan Drug Overdose Act provides legal protection from simple drug possession charges for individuals who seek emergency help during an overdose or who are at the scene when help arrives. According to Health Canada, naloxone has saved thousands of lives. Naloxone use in dogs Naloxone has been used off-label in dogs, meaning it is not formally approved in Canada for use in companion animals. However, it is commonly administered in certain situations, particularly with police working dogs who face a higher risk of accidental opioid exposure while on duty. In a 2023 study involving working dogs who had been administered fentanyl, an opioid frequently used in veterinary hospitals for pain relief and sedation, naloxone was effective in reversing sedation using either intramuscular or intranasal doses. While generally considered safe, its use should still be monitored for any adverse reaction. Administration of naloxone to your own animal or providing first aid to an animal in an emergency do not fall within the regulated practice of veterinary medicine; if naloxone is administered, the pet owner should seek immediate veterinary care. Signs of opioid poisoning Slow or absent breathing is the most critical and life-threatening sign of an opioid overdose in dogs. It may be accompanied by extreme lethargy, a blank stare, unconsciousness, unresponsiveness, pale gums, pinpoint (very small) pupils and vomiting. In humans, not every sign of an overdose needs to be present before administering naloxone. The same is true for dogs: if breathing is impaired and there is any possibility of opioid exposure, it is appropriate to administer naloxone and contact a veterinarian for further care. If you suspect your dog has ODed, administer naloxone Administer naloxone right away if you suspect your dog has overdosed. If possible, wear gloves before handling the animal. The dog should also be taken to a veterinarian as soon as possible for immediate emergency medical attention. To give naloxone in the nose, hold the dog’s snout closed, spray the medication into one nostril, and then cover the nose with a towel to reduce the chance of the dog sneezing and spreading opioid residue to the person administering. For an injectable dose, inject it in the front portion of the upper thigh into the muscle tissue. Because these methods require physical contact, wash your hands immediately afterward and avoid touching your face in case any opioid residue remains on your skin. Additional doses may be needed for larger dogs or when the amount of opioid consumed is significant, so anticipate administering a second dose. Due to the high potency of many opioids, more than one dose is often necessary to fully reverse their effects. In humans, a second dose is recommended two to three minutes after the first if there is no improvement in breathing or responsiveness. Doses can be repeated at two- to three-minute intervals until the person or animal shows signs of responsiveness or until additional medical assistance is available. In a dog’s body, naloxone is shorter-lived than many opioids, meaning overdose symptoms can return 30-90 minutes after initial improvement. So it is essential to seek immediate veterinary care and ensure the dog is monitored closely for several hours. Never perform mouth-to-snout resuscitation on a dog with a suspected opioid overdose unless you have a breathing barrier, as there is a strong chance that the dog inhaled the opioid. A study evaluating human exposure during intranasal and intramuscular naloxone treatment emphasizes always using protective equipment, such as gloves, a towel to block sneezing, and a breathing barrier for rescue breaths. Clean up thoroughly afterwards to reduce the risk of secondary opioid transfer to the human responder: wash hands and face with warm soapy water, change and wash clothing, and wash the floor and any other surfaces that might contain traces of the substance. Opioid drugs in powder or pill form cannot be absorbed through human skin, only though mucous membranes (mouth, nose and eyes). Keeping your pet safe There are several important ways to help keep your dog and other pets safe. Store medications securely: Keep all human and pet medications out of reach of pets. Recognize poisoning signs: Learn the symptoms of opioid poisoning in dogs so you can act quickly. Seek help promptly: if you suspect opioid exposure, seek immediate veterinary care. You can also contact a 24/7 resource like the Pet Poison Helpline (fee: US$89) or APSCA Poison Control hotline (fee: US$95). Be prepared: Complete naloxone training for humans and advocate for including information on dogs. Add a ready-made presentation deck to naloxone training. Know other risks: Everyday hazards, such as chocolate, grapes, cannabis and other toxic substances can also endanger your pet. Monitor surroundings: This news report describes a dog’s fentanyl overdose and naloxone reversal. Using naloxone: Naloxone does not reverse the effects of non-opioid sedatives used in veterinary medicine, or street drugs such as cocaine.

Follow prescriptions: Always give medications exactly as prescribed and consult your veterinarian if you have questions. Dispose properly: Ensure safe disposal of both human and pet unused or expired medications by returning them to a pharmacy.

Contributing funding received by Colleen Dell for the Office of the Research Chair in One Health & Wellness, University of Saskatchewan & by Barb Fornssler and Maryellen Gibson from the Saskatchewan Health Research Foundation, Mobilize Grant. Barbara Fornssler, Jennifer Loewen, and Maryellen Gibson do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.