Overview of Tramadol Hydrochloride for Canines and Felines
- Tramadol hydrochloride, known as Ultram®, is a synthetic centrally acting analgesic. Used for treating moderate to severe pain for dogs and cats.
- Its chemical name is (±)cis-2- [(dimethylamino)methyl]-1-(3-methoxyphenyl) cyclohexanol hydrochloride.
- Its mode of action is not completely understood but it appears that at least two complementary mechanisms are operating: 1) binding of parent drug and metabolite to µ-opioid receptors, and 2) weak inhibition of reuptake of norepinephrine and serotonin.
- Opioid activity is a result of low affinity binding of the parent compound and higher affinity binding of the O-demethylated metabolite (M1) to opioid receptors. M1 is up to 6 times more potent than tramadol in producing analgesia and is 200 times more potent in opioid binding.
- May take up to 2 weeks for Tramadol to to reach it’s full analgesic effect.
- Tramadol-induced antinociception is only partially reversed by naloxone.
- Tramadol is well absorbed when administered orally.
- Tramadol is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.
- This drug is not approved for use in animals by the Food and Drug Administration but it is prescribed legally by veterinarians as an extra-label drug.
Brand Names and Other Names of Tramadol Hydrochloride
- This drug is registered for use in humans only.
- Human formulations: Ultram® (Ortho-McNeil) and various generic forms.
- Veterinary formulations: None
Uses of Tramadol for Dogs and Cats
Tramadol is used for the management of moderate to severe pain. It is often used with other anti-inflammatory or pain control drugs.
Precautions and Side Effects
- While generally safe and effective when prescribed by a veterinarian, tramadol can cause side effects in some animals.
- Tramadol should not be used in animals with known hypersensitivity or allergy to this product or opioids.
- It is contraindicated in patients intoxicated with hypnotics, centrally acting analgesics, opioid or psychotropic drugs, or narcotics.
- High oral doses of tramadol over a sustained period (6 weeks to 12 months) have caused hypermotility in dogs.
- Tramadol was found to be a mild myocardial depressant when given to dogs by intravenous injection.
- Tramadol may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with tramadol.
Some possible interactions include:
- Carbamazepine increases metabolism of tramadol and decreases its analgesic efficacy.
- Quinidine interferes with the metabolism of tramadol thus altering the ratio of tramadol to M1.
- Drugs that inhibit the reuptake or metabolism of serotonin or norepinephrine, e.g. tricyclic antidepressants, SSRIs, and MAO inhibitors like deprenyl will have additive effects with respect to serotonin and/or norepinephrine when coadministered with tramadol.
- Tramadol may increase the anticoagulant effect of warfarin and digoxin toxicity.
How Tramadol is Supplied
- Ultram® tablets contain 50 mg of tramadol hydrochloride and are white in color. Inactive ingredients in the tablet are corn starch, hydroxypropyl methylcellulose, lactose, magnesium stearate, microcrystalline cellulose, polyethylene glycol, polysorbate 80, sodium starch glycolate, titanium dioxide and wax.
Dosing Information of Tramadol Hydrochloride for Dogs and Cats
- Medication should never be administered without first consulting your veterinarian.
- Doses of tramadol vary widely depending on the reason for prescribing.
- The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects.
- In dogs, Tramadol is dosed most often at 1 to 2 mg per pound (2 to 4 mg/kg) every 8 to 12 hours for post-operative pain relief. Higher doses may be used but the dose should be individualized to the lowest effective dose. The dose range for Tramadol is 2 to 5 mg per pound (4 to 10 mg/kg) orally every 8 hours.
- In cats, Tramadol is dosed most often at 0.5 to 1 mg per pound (1 to 2 mg/kg) every 12 to 24 hours.
Multiple organ systems can be affected