Metoclopramide for Dogs, Cats, and Horses

Commonly prescribed for: GI motility disorders, nausea, vomiting, diminished bladder contractility

Species: Dogs, Cats, and Horses

Therapeutic Class: GI Prokinetic, Centrally Acting Antiemetic

Metoclopramide is used in veterinary medicine to stimulate the motility of the upper GI tract. It has minimal effect on the lower GI tract and colon. Metoclopramide increases peristalsis of the small intestine and increases tone and strength of contractions in the stomach, while causing relaxation of the pyloric sphincter. Consequently, metoclopramide speeds gastric-emptying and, possibly, intestinal transit times. It does not stimulate gastric, pancreatic, or biliary secretions.

Metoclopramide acts as a central antiemetic by blocking the uptake of dopamine at the chemo receptor trigger zone in dogs. Additionally, part of its actions on the upper GI tract include increasing the sphincter pressure in the lower esophagus and reducing gastroesophageal reflux, which also may be helpful for decreasing vomiting.

Metoclopramide is well-absorbed orally. It penetrates the central nervous system (CNS) well, which may be relevant because of CNS side-effects. Metoclopramide crosses the placenta and is concentrated in milk at twice the level found in plasma. It is excreted primarily in the urine.

Metoclopramide is used in a wide variety of gastric motility disorders, including ileus and gastritis. Because so many upper GI-emptying disorders present with nausea and vomiting due to abnormal gastric-emptying, metoclopramide is particularly useful because of its effects on motility and its function as a central antiemetic. It also may be used to control nausea and vomiting in cases of renal failure, acute hepatic failure and hepatitis, and in animals undergoing chemotherapy.

Intravenous metoclopramide is used in foals to treat ileus associated with neonatal hypoxia. In these foals, metoclopramide should improve gastric-emptying and upper GI function. Metoclopramide occasionally is used in cases of post-operative ileus in the adult horse; however, neurologic side-effects limit its usefulness in adult horses.

• Dogs: Rare CNS side-effects may include either sedation or hyperactivity;
• Cats: Cats may experience hyperactivity or disorientation.
• Dogs and cats: Signs of neurotoxicity may occur in both dogs and cats at therapeutic levels. These signs usually will resolve within a few days of discontinuing the metoclopramide. Diphenhydramine may help reduce movement disorders, such as twisting movements of the face, neck, trunk, or limbs, as well as CNS depression, nervousness, restlessness, or frenzied behavior (especially in cats). Constipation may occur in both species.
• Adult horses: CNS side-effects (alternating both sedation and excitement) and colic may occur with IV administration. Side effects are less common in foals.

• Metoclopramide should not be used in animals with GI obstruction, perforation, or hemorrhage.
• Metoclopramide should not be used in animals with a history of seizures, as it may lower the seizure threshold.
• Metoclopramide should not be used in animals with pheochromocytoma.

• Metoclopramide may affect the absorption of other oral medications including cyclosporine and tetracyclines.
• Cholinergic drugs such as bethanechol may increase the effect of metoclopramide on the GI system.
• Metoclopramide may increase the CNS-depressant effects of phenothiazine tranquilizers, sedatives, narcotics, barbiturates, antihistamines, and anesthetic agents.
• Extrapyramidal effects of metoclopramide also may be increased with concurrent use of phenothiazine tranquilizers, narcotics, and butyrophenones.
• Acute hypotension may occur with IV use of metoclopramide and anesthetic drugs. Hypertension may occur with concurrent use of metoclopramide and MAO inhibitors.
• Opiate analgesics, atropine, and other anticholinergic drugs may antagonize any effects on GI motility.

• Metoclopramide has a high LD50 and, as a consequence, it is unlikely that an oral overdose will cause death.
• Overdose will cause similar but more severe clinical signs discussed under side effects.
• If the overdose was recent, the stomach should be emptied using standard protocols.
• Anticholinergics, such as diphenhydramine, may be used to decrease CNS signs.

Wedgewood provides medication options that help ensure accurate dosing, especially for hard to medicate pets. Click below for a complete list of Wedgewood’s dosing forms and strengths.

View all Metoclopramide options