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POM-V Prescription Required Companion Animal

Alizin 30 mg/ml Solution for Injection for Dogs

Active ingredient: Aglepristone

Form

Injection

Species

Dogs

Manufacturer

VIRBAC

VMD MA No.

05653/5040

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 Aglepristone

  1. 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. 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.

Prescription required

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

Clinical information

Alizin 30 mg/ml Solution for Injection for Dogs — SPC Details

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

Administer 10 mg per kg of bodyweight of aglepristone, equivalent to 0.33 ml of
veterinary medicinal
Weight of bitch3 kg 6 kg9 kg12 kg24 kg30 kg42 kgVolume of
veterinary
medicinal
product
1 ml2 ml3 ml4 ml8 ml10 ml 14 ml
Severe local reactions can be avoided if the veterinary medicinal product is
administered into the scruff of the neck. A light massage of the injection site is
recommended.

Amended pages: January 2026
In large bitches, it is recommended that a maximum of 5 ml is injected at any one
site.
This veterinary medicinal product does not contain an antimicrobial preservative.
Swab the septum before removing each dose. Use a dry, sterile needle and syringe.
Following administration of the veterinary medicinal product to dogs, abortion (or
resorption) occurs within 7 days.
The stopper can be safely punctured up to 10 times.
Do not use in dogs with impaired hepatic or renal function, in diabetic animals or in
dogs in poor health.
Do not use in dogs with either manifest or latent hypoadrenocorticism (Addison’s
disease) or in dogs with a genetic predisposition to hypoadrenocorticism.
Do not use in dogs with known hypersensitivity to aglepristone or the veterinary
medicinal product excipient.

Amended pages: January 2026
Dogs (bitches).
Very common
(>1 animal / 10
animals treated):
Injection site inflammation
, Injection site pain
2,3
Injection site oedema
, Injection site thickening
Enlarged lymph node (localised)
Anorexia, Depression
Excitation
Diarrhoea
Common
(1 to 10 animals / 100
animals treated):
Modified haematological parameters (neutrophilia,
neutropenia, thrombocytosis, elevated haematocrit,
decreased haematocrit, lymphocytosis, lymphopenia)
Modified biochemical parameters (elevated blood urea
nitrogen (BUN), elevated creatinine, hyperchloraemia,
hyperkalaemia, hypernatremia, elevated alanine
aminotransferase (ALT), elevated serum alkaline
phosphatase (SAP), elevated aspartate aminotransferase
(AST))
Uterine infection, Return to oestrus
Vomiting
Rare
(1 to 10 animals /
10,000 animals
treated):
Hypersensitivity reaction
Lack of efficacy
Very rare
(<1 animal / 10,000
animals treated,
including isolated
reports):
Injection site ulcer
Undetermined
frequency:
Physiological signs of parturition (foetal expulsion, vaginal
discharge, reduced appetite, restlessness and mammary
congestion)
Amended pages: January 2026
At the injection site, size and intensity of the reaction depending on the volume of
the veterinary medicinal product administered.
During and shortly after injection.
All local reactions are reversible and usually disappear within 28 days after
injection.
Changes are always transient and reversible.
Early return to oestrus (oestrus interval shortened by 1 to 3 months).
Accompanies abortion in bitches treated after 20 days of gestation.
Which could lead to dystocia or uterine rupture and very rarely to fatal outcome.
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 its local representative or the national
competent authority via the national reporting system. See the package leaflet for
respective contact details.
Rare cases of lack of efficacy (>0.01 % to < 0.1%) have been reported as part of the
pharmacovigilance survey. To reduce the possibility of lack of expected efficacy,
avoid the use of Alizin until after the end of oestrus and avoid new mating before the
end of oestrus.
In bitches confirmed pregnant, a partial abortion was observed in 5% of cases in field
trials. A thorough clinical examination is always recommended in order to confirm that
the uterus content is fully evacuated. Ideally, the examination should be conducted
using ultrasound. This examination should be performed 10 days after treatment and
at least 30 days after mating.
In case of partial abortion or no abortion, repeat treatment may be recommended
10 days after treatment, between day 30 and day 45 after mating. Surgery should
also be considered.

Special precautions for safe use in the target species:
In the absence of available data, the veterinary medicinal product should be used
with caution in dogs with chronic obstructive-airway disease and/or cardiovascular
disease, particularly bacterial endocarditis.
Fatalities have been reported subsequent to off-label use in seriously ill bitches with
uterine infections. A causal association is difficult to determine but is unlikely.
In up to 50 % of bitches, mating may not be followed by pregnancy. The possibility
that a bitch may therefore be treated unnecessarily should be taken into account in
evaluating the veterinary medicinal product risk-benefit ratio.
Bitches that remain pregnant despite treatment should be monitored, as viability of
the puppies may be compromised and serious complications such as dystocia and
uterine rupture could result from abortion failure.
Possible long-term effects of treatment have not been studied.
Owners should be advised to consult their veterinary surgeon if their dog shows the
following signs after treatment with the veterinary medicinal product:
-
-
Special precautions to be taken by the person administering the veterinary medicinal
product to animals:
Nor-steroids are used in humans to induce abortion. Accidental injection may be a
particular hazard to women who are pregnant, intending to become pregnant or

Amended pages: January 2026
whose pregnancy status is unknown. Care should be taken by the veterinary surgeon
when handling the veterinary medicinal product and the person restraining the dog to
avoid accidental injection. Pregnant women should administer the veterinary
medicinal product with caution. This is an oil-based veterinary medicinal product that
may cause prolonged local reactions at the site of injection. In case of accidental self-
injection, ingestion, spillage onto skin and/or eyes, seek medical advice immediately
and show the package leaflet or the label to the physician.
Women of child-bearing age should avoid contact with the veterinary medicinal
product or wear disposable plastic gloves when administering the veterinary
medicinal product.
Special precautions for the protection of the environment:
Not applicable.
In the absence of available data, a risk of drug interaction between aglepristone and
ketoconazole, itraconazole and erythromycin may exist.
As aglepristone is an anti-glucocorticoid, it might reduce the effect of glucocorticoid
treatment.
Possible interactions with other medicaments have not been studied.
Keep the vial in the outer carton in order to protect from light.
Should any apparent growth or discoloration occur, the veterinary medicinal product
should be discarded.
Not applicable.
4.

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.

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