Dogs and Cats: 0.2-0.5 mg/kg every 6-8 hours orally, IV or IM, or 1-2 mg/kg every 2-4 hours by continuous IV infusion, or approximately 0.1-0.2 mg/kg every hour.
Horses: 0.125-0.25 mg/kg/hr IC [added to IV fluids].
Metoclopramide is best given 20 minutes before a meal.
Side Effects
Side effects are rare with metoclopramide but generally stem from the ability to penetrate the blood-brain barrier. Animals predisposed to seizures (i.e., epileptics) may experience seizures, although this should not be a problem for normal animals. Use cautiously in horses because of excitement.
Some animals experience drowsiness and others will experience marked hyperactivity. Hyperactivity can be reversed with a dose of Benedryl (diphenhydramine).
Constipation has been reported as a side effect in some individuals. This is not a common side effect.
If you suspect your pet is having an adverse reaction to metoclopramide, discontinue the medication and inform your veterinarian. There is another motility modifier called cisapride (Propulsid) that may be a good alternative. This medication does not cross the blood-brain barrier and hence does not have the behavioral side effects that metoclopramide can, but it also does not reduce the sensation of nausea by this additional mechanism either.
Interactions With Other Medications
Metoclopramide should not be used with phenothiazine, tranquilizers such as acepromazine, or if there is any potential for seizures in the patient. Both medications serve to lower the threshold to seizures.
Propantheline bromide (Pro-Banthine), which is used to treat some cardiac arrhythmias, will inactivate metoclopramide.
Narcotic analgesics may negate the effects of metoclopramide.
Cautions and Contraindications
In patients with pheochromocytoma (a rare adrenal tumor) the use of metoclopramide can induce dangerously high blood pressure.
If stomach obstruction is suspected in a patient, it is best not to encourage motility and some other anti-nausea drug is preferred.
Metoclopramide crosses the placenta and into milk and is probably best avoided in pregnant or nursing mothers.
Storage and Warnings:
Store in a tight, light resistant, childproof container in a cool, dry place at room temperature away from heat and direct sunlight.
Keep this and all medication out of reach of children and pets.
Metoclopramide is very similar to the sunscreen ingredient PABA. Humans allergic to sunscreens should avoid contact with metoclopramide.