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Rompun 100 mg/mL Injectable (Canada)

This page contains information on Rompun 100 mg/mL Injectable for veterinary use.
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  • Rompun 100 mg/mL Injectable Indications
  • Warnings and cautions for Rompun 100 mg/mL Injectable
  • Direction and dosage information for Rompun 100 mg/mL Injectable

Rompun 100 mg/mL Injectable

This treatment applies to the following species:
Manufacturer: Bayer



Sedative and Analgesic

For Use in Horses Only

DIN 02169606



Rompun® (Xylazine) is supplied in 50 mL multiple-dose vials as a sterile solution.

Each mL contains 100 mg Rompun (xylazine base equivalent), 0.9 mg methylparaben, 0.1 mg propylparaben, sterile water; citric acid and sodium citrate for pH adjustments to 5.5 ± 0.3.

Active Ingredient

xylazine 2(2,6-Dimethylphenylamino)-4H-5,6-dihydro-1,3 thiazine hydrochloride

(equivalent to 10% base)


Inert Ingredients:





Rompun is a potent sedative and analgesic as well as a muscle relaxant. Its sedative and analgesic activity is related to central nervous system depression. Its muscle-relaxant effect is based on inhibition of the intraneural transmission of impulses in the central nervous system. The principal pharmacological activities develop within 10 to 15 minutes after intramuscular injection and within 3 to 5 minutes following intravenous administration.

A sleeplike state, the depth of which is dose-dependent, is usually maintained for 1 to 2 hours, while analgesia lasts from 15 to 30 minutes. The centrally-acting muscle relaxant effect causes relaxation of the skeletal musculature, complementing sedation and analgesia. In animals under the influence of Rompun, the respiratory rate is reduced as in natural sleep. Following treatment with Rompun, the heart rate is decreased and a transient change in the conductivity of the cardiac muscle may occur, as evidenced by a partial atrioventricular block. This resembles the atrioventricular block often observed in normal horses1,2,3,4. Although a partial A-V block may occasionally occur following intramuscular injection of Rompun, the incidence is less than when it is administered intravenously. Intravenous administration of Rompun causes a transient rise in blood pressure, followed by a slight decrease.

Rompun has no effect on blood clotting time or other hematologic parameters.

In limited tests, Rompun has been tolerated in horses at 10 times the recommended dose. However, doses of this magnitude produce muscle tremors and long periods of sedation.

Rompun 100 mg/mL Injectable Indications

Rompun should be used in horses when it is desirable to produce a state of sedation accompanied by a shorter period of analgesia. It has been used successfully as follows:

1. Diagnostic procedures - oral and ophthalmic examinations, abdominal palpation, rectal palpation, vaginal examination, catheterization of the bladder and radiographic examinations.

2. Orthopedic procedures, such as application of casting materials and splints.

3. Dental procedures.

4. Minor surgical procedures of short duration such as debridement, removal of cutaneous neoplasms and suturing of lacerations.

5. To calm and facilitate handling of fractious animals.

6. Therapeutic medication for sedation and relief of pain following injury or surgery.

7. Major surgical procedures:

a. When used as a preanesthetic to general anesthesia.

b. When used in conjunction with local anesthetics.

Dosage and Administration

1. Dosage: Horses

Intravenously - 0.5 mL/100 lbs body weight (Equivalent to 0.5 mg/lb or 1.1 mg/kg)

Intramuscularly - 1.0 mL/100 lbs body weight (Equivalent to 1 mg/lb or 2.2 mg/kg)

Following injection of Rompun, the animal should be allowed to rest quietly until the full effect has been reached. These dosages produce sedation which is usually maintained for 1 to 2 hours and analgesia which lasts for 15 to 30 minutes.

2. Preanesthetic to Local Anaesthesia: Rompun at the recommended dosages can be used in conjunction with local anesthetics such as procaine or lidocaine.

3. Preanesthetic to General Anaesthesia: Rompun, at the recommended dosage rates, produces an additive effect to central nervous system depressants such as pentobarbital sodium, thiopental sodium and thiamylal sodium. Therefore, the dosage of such compounds should be reduced and administered to the desired effect. In general, only 1/3 to 1/2 of the calculated dosage of the barbiturates will be needed to produce a surgical plane of anesthesia. Post anesthetic or emergence excitement has not been observed in animals preanesthetized with Rompun. Rompun has been used successfully as a preanesthetic agent for pentobarbital sodium, thiopental sodium, thiamylal sodium, nitrous oxide, ether, halothane, and methoxyflurane anesthesia.

Sides Effects: Horses

Rompun used at recommended dosage levels may occasionally cause slight muscle tremors, bradycardia with partial A-V heart block and a reduced respiratory rate. Movement in response to sharp auditory stimuli may be observed.

Following repeated intramuscular injection at the same site, a swelling may occur and such swelling may persist for several weeks.

Rompun 100 mg/mL Injectable Caution: Horses

Careful consideration should be given before administering to horses with significantly depressed respiration, severe pathologic heart disease, advanced liver or kidney disease, severe endotoxic or traumatic shock.

Do not use Rompun in conjunction with tranquilizers.

Since an additive effect results from the use of Rompun and the barbiturate compounds, it should be used with caution with these central nervous system depressants. Products known to produce respiratory depression or apnea, such as thiamylal sodium, should be given at a reduced dosage, and, when injected intravenously, should be administered SLOWLY. When intravenous administration is desired, avoid perivascular injection in order to achieve the desired effect.

Intracarotid Arterial Injection Should Be Avoided. As with many compounds, including tranquilizers, immediate violent seizures followed by collapse may result from inadvertent administration into the carotid artery. Although the reaction with Rompun is usually transient and recovery may be rapid and complete, special care should be taken to assure that the needle is in the jugular vein rather than the carotid artery.

Bradycardia and an arrhythmia in the form of incomplete atrioventricular block have been reported following Rompun administration. Although clinically the importance of this effect is questioned1,2,3,4, a standard dose of atropine given prior to or following Rompun will greatly decrease the incidence.

Following the use of Rompun, veterinarians and attendants should continue to use care and appropriate animal handling techniques, since conscious animals, although sedated, are capable of inflicting personal injury.


Rompun has been tolerated in horses at 10 times the recommended dose. However, doses of this magnitude produced muscle tremors and long periods of sedation with careful surveillance necessary during the recovery period.



This drug is for use in horses only.


Do not store below 4 °C or above 30 °C.


1. Detweiller, D.K.: The Diagnosis and Significance of Cardiac Arrhythmias in Progress in Equine Practice. Edited by E.J. Catcott and J.F. Smithcors. American Veterinary Publications, Inc., Santa Barbara, California and Wheaton, Illinois, (1966), 280-281.

2. Glazier, D.B.: Atrioventricular Heart Block. Irish Vet. J., Vol. 12 (1958): 194-198.

3. Holmes, J.R., Alps, B.J.: Observations on Partial Atrioventricular Heart Block in the Horse. Can. Vet. J., Vol. 7, No. 12 (1966): 280-290.

4. Smetzer, D.L., Smith, C.R., Sentra, T.: Second Degree Atrioventricular Block in the Horse. Am. J. Vet. Res., Vol. 30, No. 6, (1969), 933-946.

Bayer, Bayer Cross, and Rompun are registered trademarks of Bayer AG used under license.

Bayer HealthCare, Bayer Inc., Animal Health Division, 2920 Matheson Boulevard East, Mississauga, ON L4W 5R6

08939937, R.0

September, 2005




NAC No.: 1223024.2

Animal Health

Telephone:   905-282-5550 or 800-62BAYER (800-622-2937)
Technical Service:   888-663-5326
Order Desk:   800-387-9179
Order Desk Fax:   800-361-3306
Fax:   905-282-5725
Every effort has been made to ensure the accuracy of the Rompun 100 mg/mL Injectable information published above. However, it remains the responsibility of the readers to familiarize themselves with the product information contained on the Canadian product label or package insert.

Copyright © 2016 North American Compendiums. Updated: 2016-09-30