Sedative - Analgesic
Xylazine Injection is a sedative, analgesic and muscle relaxant for use in horses and Cervidae (Fallow Deer, Mule Deer, Sika Deer, White-Tailed Deer and Elk). Xylazine can be given by intramuscular, intravenous or subcutaneous routes and by dart gun.
Xylazine Injection should be used in horses and
Cervidae when it is desirable to produce a state of
sedation accompanied by a shorter period of analgesia.
For Use in Horses and Cervidae (Fallow Deer, Mule
Deer, Sika Deer, White-Tailed Deer and Elk)
Horses: Xylazine (TranquiVed, AnaSed, Rompun and others) 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.
Cervidae: Xylazine may be used for the following:
1. To calm and facilitate handling of fractious animals.
2. Diagnostic procedures.
3. Minor surgical procedures.
4. Therapeutic medication for sedation and relief of pain
following injury or surgery.
5. As a preanesthetic to local anesthesia. Xylazine
at the recommended dosages can be used in conjunction with local
anesthetics, such as procaine or lidocaine.
CAUTION
Federal law restricts this drug to use by or on the order of
a licensed veterinarian. Do not use in Cervidae
less than 15 days before or during the hunting season.
DESCRIPTION
Xylazine is supplied in 50 ml multiple dose
vials as a sterile solution. Each ml contains 100 mg xylazine.
PHARMACOLOGY
Xylazine, a non-narcotic compound, is a
sedative and analgesic as well as 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 in horses and Cervidae, and
within 3 to 5 minutes following intravenous administration in horses.
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 horses and Cervidae under the
influence of xylazine, the respiratory rate is reduced as in
natural sleep. Following treatment with xylazine, 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 horses.
Partial A-V block may occasionally occur following intramuscular injection
of xylazine. When given intravenously in horses, the incidence
of partial A-V block is higher. Intravenous administration causes a
transient rise in blood pressure in horses, followed by a slight decrease.
Xylazine has no effect on blood clotting time
or other hematologic parameters.
DOSAGE AND ADMINISTRATION
Horses:
1. Dosage: Intravenously-0.5 ml/100 lbs body weight (0.5
mg/lb)
Intramuscularly-1.0 ml/100 lbs body weight (1.0 mg/lb)
Following injection of Xylazine, 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 Anesthesia: Xylazine
at the recommended dosages can be used in conjunction with local
anesthetics, such as procaine or lidocaine.
3. Preanesthetic to General Anesthesia: Xylazine
at the recommended dosage rates produces an additive effect to central
nervous system depressants such as pentobarbital sodium, thiopental sodium
and thiamyl 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 Xylazine.
Xylazine has been used successfully as a
preanesthetic agent for pentobarbital sodium, thiopental sodium, thiamylal
sodium, nitrous oxide, ether, halothane, glyceryl guaiacolate and
methoxyflurane anesthesia.
Cervidae:
Administer intramuscularly, either by hand syringe or
syringe dart, in the heavy muscles of the croup or shoulder.
Dosage Range:
Fallow Deer (Dama dama)-2.0 to 4.0
mL/100 lbs body weight (2.0 to 4.0 mg/lb).
Mule Deer (Odocoileus hemionus)-1.0
to 2.0 mL/100 lbs body weight (1.0 to 2.0 mg/lb).
Sika Deer (Cervus nippon)-1.0 to
2.0 mL/100 lbs body weight (1.0 to 2.0 mg/lb).
White-Tailed Deer (Odocoileus
virginianus)-1.0 to 2.0 mL/100 lbs body weight (1.0 to 2.0 mg/lb).
Elk (Cervus canadensis)-0.25 to 0.5
mL/100 lbs body weight (0.25 to 0.5 mg/lb).
Following injection of Xylazine, 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.
SIDE EFFECTS
Xylazine in horses and
Cervidae, 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.
In horses, sweating, rarely profuse, has been reported
following administration. In Cervidae, salivation,
various vocalizations (bellowing, bleating, groaning, grunting, snoring) on
expiration, audible grinding of molar teeth, protruding tongue and elevated
temperatures have also been noted in some cases.
PRECAUTIONS
Careful consideration should be given before administering
to horses and Cervidae with significantly depressed
respiration, severe pathologic heart disease, advanced liver or kidney
disease, severe endotoxic or traumatic shock and stress conditions such as
extreme heat, cold, high altitude or fatigue.
Do not use Xylazine in conjunction with
tranquilizers.
Analgesic effect is variable, and depth should be carefully
assayed prior to surgical/clinical procedures. Variability of analgesia
occurs most frequently at the distal extremities of horses and
Cervidae. In spite of sedation, the
practitioner and handlers should proceed with caution since defense
reactions may not be diminished.
Horses:
Since an additive effect results from the use of Xylazine 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 of Xylazine is desired,
avoid perivascular injection in order to achieve the desired effect. Studies
have shown negligible evidence of tissue irritation, however, following
perivascular injection of xylazine.
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
Xylazine 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 arrhythmia in the form of incomplete
atrioventricular block have been reported following xylazine administration.
Although clinically the importance of this effect is questioned,
a standard dose of atropine given prior to or following xylazine will
greatly decrease the incidence.
Sedation for transport is most successful if actual
transportation is begun after the full effect of the drug has been reached
and the animal's stability is maintained while standing. In addition, it
should be noted that animals under the influence of xylazine can be aroused
by noise or other stimuli and this may increase the risk of injury.
Cervidae:
As in all ruminants, it is preferable to administer Xylazine to fasted Cervidae as a
safeguard against aspiration of food material into the lungs and/or bloat
during deep sedation.
Care should be taken to administer Xylazine in
the heavy muscles of the croup or shoulder. Injections given subcutaneously,
intraperitoneally or into fat deposits will give unpredictable results.
Intra-arterial injection should be avoided, as with many
compounds, including tranquilizers, immediate violent seizures followed by
collapse may result from inadvertent administration into an artery.
The animal should not be disturbed during induction or until
the full effect of the drug has been reached which is usually 10 to 15
minutes following injection.
The usual time to initial effect of the drug is 2 to 5
minutes. The administrator of the drug should be fully cognizant of this
interval prior to administration of drug to free-ranging deer or elk,
especially at night or in heavily wooded areas.
If the animal has been underdosed (faulty injection or
miscalculation on weight) it is advisable to wait one hour before
administering a second dose.
Adequate ventilation- especially in cages or crates- is
mandatory; keep head and neck in position to insure patient air passage and
to prevent aspiration of stomach contents.
During sedation, animals should be prevented from assuming
lateral recumbency. A sternal recumbent position is desirable.
While under the effects of Xylazine, the animal
should be protected from extreme hot or cold environments.
Efforts should be made to prevent patient from rising until
almost complete recovery is attained.
The transportation of Cervidae
given Xylazine should be carefully monitored to prevent
excessive struggling, injury or death.
Hyperthermic reactions may occur, especially if the subject
is in a highly excited state when the drug is administered. Hosing the head
and entire body with cold water has usually proven to be an effective
deterrent.
The safety of Xylazine has not been
demonstrated in pregnant Cervidae. Avoid use during
the breeding season.
Cervidae should be observed closely
until all of the sedative effects of Xylazine are gone.
Care should be taken at all times when administering
Xylazine to Cervidae. This is due to
the method of administration (usually darting), the difficulty in estimating
body weights and the accepted theory that wild animals are more
unpredictable in their response to sedatives and analgesics than the
domesticated species.
SAFETY
Xylazine is tolerated at 10 times the
recommended dose in horses and at doses above the recommended range in
Cervidae. However, some elevated doses produced
muscle tremors and long periods of sedation.
WARNING
This drug should not be administered to domestic
food-producing animals. Not for use in horses intended for food.
Avoid accidental administration to humans. Should such
exposure occur, notify a physician immediately. Artificial respiration may
be indicated.
In Cervidae, occasional
capture-associated deaths occur. Clinical trials reveal a mortality rate of
approximately 3.5% attendant with the administration of xylazine.
HOW SUPPLIED
Xylazine 100 mg/mL for intravenous or
intramuscular use is available in 50 mL multiple dose vials.
Store at controlled room temperature (15° to 30°C or 59° to
86°F).
NOT FOR HUMAN USE.
KEEP OUT OF REACH OF CHILDREN