POM-V Prescription Required Companion Animal

Xylexx 20 mg/ml Solution for Injection for Cattle, Horses, Dogs and Cats

Active ingredient: Xylazine

Form

Injection

Species

Cats Cattle Dogs Horses

Manufacturer

Alfasan Nederland B.V.

VMD MA No.

36408/3007

What it's used for

Premedication in combination with an anaesthetic.

Full indications, dosage and side effects ↓

View official SPC (PDF)

The prescription itself has a price. See what practices near you charge for a consultation and the written prescription fee.

Paying less for Xylazine

1

Ask your vet for a written prescription

They must provide one on request. Under the CMA Order the fee is capped at £21 from 2027.
2

Fill it at a registered online retailer

The CMA found online pharmacies 50–60% cheaper than practice dispensing on common medicines — typically £200–£300 a year.

Your prescription rights → VMD register of retailers →

Prescription required

Your vet must provide a written prescription on request. You can then purchase from any licensed online retailer.

Clinical information

Xylexx 20 mg/ml Solution for Injection for Cattle, Horses, Dogs and Cats — SPC Details

Source: VMD Summary of Product Characteristics (SPC). Last updated 27 Mar 2026.

Premedication in combination with an anaesthetic.

Horses: intravenous use.
Dogs: intramuscular use.
Cats: intramuscular or subcutaneous use.
To ensure a correct dosage body weight should be determined as accurately as
possible.
The intravenous injection should be given slowly, especially in horses.
This veterinary medicinal product is for administration only by a veterinarian or under
their supervision.
Cattle (i.v., i.m.)
Dosage cattleDose levelxylazine
(mg/kg)
xylazine 20
mg/ml
(ml/100 kg)
xylazine 20
mg/ml
(ml/500 kg)
A. IntramuscularI0.050.251.25II0.10.52.5III0.215IV0.31.57.5B. IntravenousI0.016-0.0240.08-0.120.4-0.6II0.034-0.050.17-0.250.85-1.25III0.066-0.100.33-0.51.65-2.5
Dosage I: Sedation with slight reduction of muscle tone. The cattle are still able to
stand.
Dosage II: Sedation with pronounced reduction of muscle tone and slight
analgesia. The cattle mostly remain able to stand but may also lie down.
Dosage III: Deep sedation, further reduction in muscle tone, partial analgesia.
The cattle lie down.
Dosage IV: Very deep sedation with a pronounced reduction in muscle tone,
partial analgesia. The cattle lie down.
Horses (i.v.)
Dosage:
medicinal product per 100 kg bodyweight).
Dogs (i.m.)
Dosage: single injection of 0.5-3 mg xylazine per kg body weight. (0.25-1.5 ml
veterinary medicinal product per 10 kg bodyweight).
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Cats (i.m., s.c.)
Dosage:
veterinary medicinal product per kg bodyweight).
The stopper can be broached up to 30 times.

Do not use in cases of hypersensitivity to the active substance or to any of the
excipients.
Do not use in animals with gastrointestinal obstruction, as it is a muscle relaxant and
the properties of the veterinary medicinal product appear to enhance the effects of an
obstruction, and because of the risk of vomiting.
Do not use in cases of pulmonary disease (breathing deficiency) or cardiac disorders
(especially in case of ventricular arrhythmia).
Do not use in cases of impaired liver or renal function.
Do not use in cases of predetermined history of seizures.
Do not use in cases of hypotension and shock.
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Do not use in animals with diabetes mellitus.
Do not administer simultaneously with sympathomimetic amines (e.g. epinephrine).
Do not use in calves less than 1 week of age, foals less than 2 weeks of age or
puppies and kittens under 6 weeks of age.
Do not use during the last stage of pregnancy (danger of premature birth), except at
parturition (see section 3.7).

Cattle:
Undetermined frequency
(cannot be estimated from the
available data:
Injection site irritation
;
Hypothermia
, hyperthermia
;
Rumen atony, bloated, regurgitation, loose stool
,
hypersalivation, tongue disorder
;
Respiratory depression, respiratory arrest,
snoring, stridor
;
Hypotension, bradycardia
, arrhythmia
;
Polyuria;
Premature parturition; uterine disorder
, penile
prolapse
.
reversible.
thermoregulation can be influenced and consequently body temperature can
decrease or increase dependant on the ambient temperature.
for 24 hours after high doses of xylazine.
atony.
nasal stridor.
can be severe.
reduced implantation of the ovum.
In cattle, adverse effects are generally more pronounced after intramuscular
administration compared to intravenous.
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Horses:
Rare
(1 to 10 animals / 10,000
animals treated):
Abnormal behaviour
;Very rare
(<1 animal / 10,000 animals
treated, including isolated
reports):
Colic
2,4
, digestive tract hypomotility
3,4
;Undetermined frequency
(cannot be estimated from the
available data:
Injection site irritation
;
Ataxia, muscle tremor
, involuntary movement
;
Penile prolapse
;
Hypothermia
, hyperthermia
;
Hypotension
, hypertension
, bradycardia
,
arrhythmia
;
Increased sweating
;
Frequent urination;
Respiratory depression, respiratory arrest,
decreased respiratory rate.
violent reactions.
mild.
temporarily.
to prevent this, horses should not consume any feed after sedation until the effect
has completely subsided.
reversible.
in response to sharp auditory or physical stimuli.
thermoregulation can be influenced and consequently body temperature can
decrease or increase dependant on the ambient temperature.
following administration, a transient rise followed by a fall in blood pressure usually
occurs.
can be severe.
as the effects of the sedation are wearing off.
Dogs, cats:
Rare
(1 to 10 animals / 10,000
animals treated):
Bloated
;Very rare
(<1 animal / 10,000 animals
treated, including isolated
reports):
Cardio-respiratory disorders
(cardiac arrest
,
dyspnoea
, bradypnea
, pulmonary oedema
);

Neurological disorders
(seizure, prostration
,
pupil disorder
, tremor
);
Undetermined frequency
(cannot be estimated from the
available data:
Injection site irritation
;
Bradycardia
4,5
, hypotension, arrhythmia
;
Hypothermia
, hyperthermia
;
Involuntary movement
, muscle tremor;
Hyperglycaemia;
Hypersalivation, vomiting
;
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Polyuria;
Premature parturition
, uterine contraction
;

Respiratory arrest
.
in susceptible dog breeds with a large chest (Great Dane, Irish Setter).
in anaesthetized animals, mainly during and after the recovery period.
reversable.
with AV-block.
can be severe.
thermoregulation can be influenced and consequently body temperature can
decrease or increase dependant on the ambient temperature.
in response to sharp auditory stimuli.
during the onset of sedation, especially when the animals have just been fed.
in cats.
In dogs, adverse effects are generally more pronounced after subcutaneous
administration compared to intramuscular and the effect (efficacy) can be less
predictable.
Reporting adverse events is important. It allows continuous safety monitoring of a
veterinary medicinal product. Reports should be sent, preferably via a veterinarian, to
either the marketing authorisation holder or the national competent authority via the
national reporting system. See the package leaflet for respective contact details.

Cattle:
•
remain standing at the lower doses, but some animals may lie down. At the
highest recommended doses, most animals will lie down, and some animals may
lapse into lateral recumbency.
•
may result in bloat. It is advisable to withhold feed and water in adult cattle for
several hours before administration of xylazine. Fasting in calves might be
indicated but should only be done at the discretion of a benefit/risk assessment
made by the responsible veterinarian.
•
the period of sedation, therefore cattle must be closely watched during the
recovery period: the animals should be maintained in sternal recumbency.
•
mg/kg body weight (respiratory and circulatory failure). Therefore, very precise
dosing is required.
•
be the subject of a benefit/risk assessment. This assessment should consider the
composition of the veterinary medicinal products, their dose and the nature of the
surgery. Recommended dosages are likely to vary according to the choice of the
anaesthetic combination.
Horses:
•
horses with colic that are not responsive to analgesics. The use of xylazine
should be avoided in horses with caecal malfunction.
•
whenever possible the drug should be administered in the place where the
treatment/investigation is going to take place.
•
to horses susceptible to laminitis.
•
dyspnoea.
•
•
be the subject of a benefit/risk assessment. This assessment should consider the
composition of the veterinary medicinal products, their dose and the nature of the
surgery. Recommended dosages are likely to vary according to the choice of the
anaesthetic combination.
AN: 00576/2021Page 3 of 10
Dogs and cats:
•
undesirable for upper gastro-intestinal radiographs, because it promotes filling of
the stomach with gas and makes interpretation less certain.
•
threatening dyspnoea.
•
be the subject of a benefit/risk assessment. This assessment should consider the
composition of the veterinary medicinal products, their dose and the nature of the
surgery. Recommended dosages are likely to vary according to the choice of the
anaesthetic combination.

Special precautions for safe use in the target species:
•
•
•
maintaining the animal in sternal recumbency.
•
animals before use of the veterinary medicinal product.
•
highly excitable animals may require a relatively high dose.
•
•
and dogs. It is advisable to fast dogs and cats for 12 hours prior to surgery; they
may have free access to drinking water.
•
bradycardia effects.
•
•
effect has been reached.
•
keep animals warm at low temperatures.
•
or general anaesthesia.
•
cautiously in procedures involving the distal extremities and in standing
castrations in the horse.
•
cardiac and respiratory function, also in the post-operative phase) and should be
segregated to avoid bullying.
•
veterinary medicinal product is intended to be used in young animals below these
age-limits, a benefit/risk assessment should be made by the veterinarian.
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
This veterinary medicinal product is a sedative. Care should be taken to avoid
accidental self-injection.
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In the case of accidental oral intake or self-injection, seek medical advice
immediately and show the package leaflet to the doctor, but DO NOT DRIVE, as
sedation and changes in blood pressure may occur.
Avoid skin, eye or mucosal contact. In the case of accidental contact of the veterinary
medicinal product with the skin or eyes, rinse with large amounts of fresh water.
Remove contaminated clothes that are in direct contact with the skin. If symptoms
occur, seek medical advice.
If pregnant women handle the veterinary medicinal product, special caution should be
observed not to self-inject as uterine contractions and decreased foetal blood
pressure may occur after accidental systemic exposure.
Advice to the physician:
Xylazine is an α2-adrenoreceptor agonist. Symptoms after absorption may involve
clinical effects including dose-dependent sedation, respiratory depression,
bradycardia, hypotension, a dry mouth, and hyperglycaemia. Ventricular arrhythmias
have also been reported. Respiratory and haemodynamic symptoms should be
treated symptomatically.
Special precautions for the protection of the environment:
Not applicable.

Other CNS depressant agents (barbiturates, narcotics, anaesthetics, tranquillizers,
etc.) may cause additive CNS depression if used with xylazine. Dosages of these
agents may need to be reduced. Xylazine should therefore be used cautiously in
combination with neuroleptics or tranquillizers. Xylazine should not be used in
combination with sympathomimetic drugs such as epinephrine as ventricular
arrhythmia may follow.
The concurrent intravenous use of potentiated sulphonamides with
been reported to cause cardiac arrhythmias which may be fatal. Whilst no such
effects have been reported with this veterinary medicinal product, it is recommended
that intravenous administration of trimethoprim / sulphonamide containing veterinary
AN: 00576/2021Page 7 of 10
medicinal products should not be undertaken when horses have been sedated with
xylazine.

Do not refrigerate or freeze.

Cattle:
Meat and offal: 1 day.
Milk: zero hours.
Horses:
Meat and offal: 1 day.
Not authorised for use in mares producing milk for human consumption.

This information is sourced from the official Summary of Product Characteristics (SPC) published by the Veterinary Medicines Directorate (VMD). It is provided for informational purposes only and does not replace professional veterinary advice. Always consult your vet before administering any medication.