Major Uses

Morphine is an opiate analgesic that is used to treat acute pain in animals such as dogs, cats, horses, swine, sheep, and goats. It can also be used as a pre-anesthetic agent in dogs and swine. Morphine is also an effective antitussive, antidiarrheal, and adjunctive therapy for some cardiac abnormalities.

Common Precautions

Morphine should be used cautiously in patients with hypothyroidism, adrenocortical insufficiency, severe renal insufficiency, and in geriatric or disabled patients. It should not be used in patients recovering from toxic ingestion until the toxin is completely removed from the GI tract. Caution should be exercised when using morphine in patients suffering from head injuries, increased intracranial pressure, acute abdominal conditions, and acute uremia.

Negative symptoms associated with morphine commonly involve respiratory functions. For example, decreased tidal volume, depressed cough reflex, and drying of respiratory secretions may occur. When rapidly administered, some patients suffer from hypotension and panting. Other effects can include nausea, vomiting, and decreased intestinal peristalsis.

Morphine should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if an overdose is suspected, the symptoms of which include respiratory and CNS depression, cardiovascular collapse, hypothermia, skeletal muscle hypotonia, CNS excitability, and seizures.


Morphine should be kept at room temperature in a tight, light resistant, childproof container. It should be stored where children and pets will not be able to reach it. It should also be kept away from conditions that could cause freezing. If the product darkens in color, it has been exposed to light for too long and should not be used.


A typical dose of morphine for dogs ranges from .05-2 mg/kg. For cats, a typical dose can range from between .02-2 mg/kg. Horses require doses ranging from .1-.2 kg/mg. If a dose is forgotten, it should be administered as soon as possible. If the next scheduled dose is close, the missed dose should be skipped and the regular dose should be administered. Two doses should not be given at the same time.

Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.

This information is for general reference only and should not be used for the diagnosis or treatment of any condition of your pet. It's intended as a general reference, this information may not include all possible uses, precautions, directions, reactions (including allergic), drug interactions, or withdrawal times. Always consult your local veterinarian and have your pet examined for any advice concerning the diagnosis and treatment of your pet, including which products and doses are most appropriate. Any trademarks are the property of their respective owners. VetDepot is not a pharmacy. All prescription products are dispensed by our Pharmacy Partner. Article last updated 2/2014.