Major Uses

Romifidine hydrochloride is a sedative and analgesic medication for use in horses. It is primarily used to facilitate handling, minor surgical procedures, and clinical examinations. The drug may also be used as a preanesthetic prior to use of general anesthesia. It may sometimes be administered for reasons other than these.

Romifidine hydrochloride is an alpha-2 agonist and is only for use in horses. In countries outside the United States, the drug is sometimes approved for use in cats and dogs.

Common Precautions

A number of side effects are possible with proper use of romifidine hydrochloride, including hypotension, cardiac arrhythmias, hypertension, ataxia, piloerection, salivation, urination, stridor, sweating, penile relaxation, flatulence, muscle tremors, lowering of the head, decreased gastrointestinal motility, and mild colic. Excitation is also possible.

Romifidine hydrochloride is not for use in animals intended to be used as food. The drug should not be used in animals with cardiac conditions, respiratory disease, dehydration, liver disease, or kidney disease. It should be used cautiously in animals with colic and in those that are pregnant or nursing. Use of IV potentiated sulfonamides in anesthetized or sedated horses can cause potentially fatal cardiac dysrhythmias.

Although romifidine hydrochloride causes deep sedation, horses may still respond to external stimuli with kicking and other defensive actions. Routine safety measures must be used with these actions in mind.

Romifidine hydrochloride may interact with other drugs and supplements, including phenothiazines, opiates, intravenous potentiated sulfonamides, and other sedatives and alpha-2 agonists. Romifidine hydrochloride should not be used in animals with a known allergy or hypersensitivity to the drug. Any known or suspected overdose should be reported to a veterinarian right away.


Romifidine hydrochloride should be stored in its original packaging, out of the reach of children and animals, and at room temperature.


Romifidine hydrochloride is available as injectable solution for IV administration. For sedation and analgesia, romifidine hydrochloride is typically administered as a single IV injection in the dosage range of 0.4 to 1.2 ml/kg body weight. The onset of action occurs within 5 minutes. For preanesthesia, a single IV injection of 1.0 ml/100 kg body weight is typical.

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.

If a dose of romifidine hydrochloride is missed, it should be administered as soon as possible. If it is almost time for the next dose, the missed dose should be skipped and the normal schedule resumed. Two doses of this medication should not be given at once.

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.