Opioids For Small Animals

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What Are Opioids for Small Animals?

Opioids for small animals are powerful painkillers that alter the way the body perceives pain. These drugs have been used for decades to give relief to chronic pain sufferers, but they have also found their way into veterinary medicine. The question is, how does opioid use in animals differ from its use in humans?

Opioids are highly addictive substances that can cause dangerous side effects if misused. This is why it’s vital for veterinarians to work closely with clients who want to give these drugs as a form of comfort therapy. It’s important that vets have a thorough understanding of how opioids work in the body, as well as the possible side effects.

infographic on opioids for small animals

Common Uses of Opioids in Small Animals

Opioids are commonly used as a form of pain management for dogs and cats with natural pain levels, as well as those who suffer from chronic or severe pain. In recent years, these drugs have been increasingly used by veterinarians to provide relief from pain for experimental surgeries.

Experts estimate that more than 50 million Americans and 700 million people worldwide use some form of opioid medications for chronic or severe pain. The main goal of this therapy is to reduce the amount of pain the pet is experiencing.

Opioids can also be used before veterinary procedures like spaying and neutering, as well as minor medical procedures such as dental, eye, and ear care. Veterinarians may also administer these drugs to pets with cancer or other serious illnesses in order to manage their pain while they undergo treatment.

Although opioids have been shown to relieve the pain of a variety of conditions, these drugs have a high risk for abuse. In fact, side effects from opioid use can be extremely dangerous and even deadly in some cases.

It’s not uncommon for animals to develop a dependency on these potent medications. They often depend on opioids even when they don’t need them. This can lead to fatal consequences such as overdose and accidental poisoning.

opioid addiction

The Small Animal Opioid Connection in Veterinary Medicine

Veterinarians, just like their human counterparts, are subject to the same type of pressure that can influence dangerous prescribing practices. This is why it’s vital for vets to work closely with animal owners when evaluating the use of opioids. These drugs must be prescribed with caution so that animals don’t develop a dependency on them.

According to the American Veterinary Medical Association (AVMA), there are several indications when it comes to therapies involving opioids in animals.

Opioids For Small Animals

Morphine (mu agonist)

Use: moderate/severe pain
Higher dose: good sedation

  • Causes vomiting
  • Risk of histamine reaction if given IV
  • Time to effect: 20-30 minutes
  • Duration of effect: 2-4 hours
  • Dose: 0.1-1.0 mg/kg IM

Methadone (mu agonist)

Use: moderate/severe pain
Not so good sedation if used alone

  • No vomiting
  • Time to effect: 20-30 minutes
  • Duration of effect: 2-4 hours
  • Dose: 0.1-1.0 mg/kg IM

Pethidine (mu agonist)

Use: moderate/severe pain
Questionable sedation if used alone

  • Risk of histamine reaction if given IV
  • Time to effect: 15-20 minutes
  • Duration of effect: 1 hour
  • Dose: 1-5 mg/kg IM

Fentanyl (mu agonist)

Good sedation with high doses

  • Time to effect: 5 minutes IV
  • Duration of effect: up to 15 minutes IV
  • Dose IV: 2-10 mcg/kg (when awake) 1-2 mcg/kg (anesthetized), 2-10 mcg/kg/hour (infusion)

Butorphanol (agonist/antagonist)

Use: mild/moderate pain
Good sedation with high doses

  • Time to effect: 10-15 minutes (IM)
  • Duration of effect: 1-2 hours (IM)
  • Dose: 0.1-0.4 mg/kg IM

Buprenorphine(partial agonist)

Use: mild/moderate pain
May be used as effective sedation in cats

  • Time to effect: 45-60 minutes
  • Duration of effect: 4-8 hours (increasing the dose will increase the duration)
  • Dose: 0.02-0.05 mg/kg IM

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