POM-V Prescription Required Companion Animal

Chorulon 1500 IU Powder and Solvent for Solution for Injection

Active ingredient: Chorionic Gonadotrophin

Form

Injection

Species

Cattle Dogs Horses

Manufacturer

Intervet International B.V.

VMD MA No.

06376/4090

What it's used for

- induction of ovulation in mares and bitches. - cases of cystic ovaries in cows and heifers. - anoestrus in mares and bitches. - delayed ovulation, prolon...

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 Chorionic Gonadotrophin

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.

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Prescription required

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

Clinical information

Chorulon 1500 IU Powder and Solvent for Solution for Injection — SPC Details

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

- induction of ovulation in mares and bitches.
- cases of cystic ovaries in cows and heifers.
- anoestrus in mares and bitches.
- delayed ovulation, prolonged pro-oestrus in bitches.
- deficiency in libido in male dogs.

Reconstitute with the solvent provided, ensuring the freeze-dried plug is fully
dissolved. Reconstituted solution is colourless.
Administer by intramuscular or intravenous injection, observing the usual
aseptic precautions.
SpeciesIndicationDosage and administrationCow, heiferRepeated failure of conception
Cystic ovarian disease
(anoestrus, prolonged oestrus,
nymphomania)
Enhancement of luteal
function
1 500 IU – IM or IV at AI or
mating.
3 000 IU – IV.
1 500 IU – IM 12 days after
insemination or mating.
MareSuboestrus (follicles > 2 cm in
diameter)
Induction of ovulation
1 500 - 3 000 IU – IM or IV,
repeat after 2 days if
necessary.
1 500 - 3 000 IU – IM or IV 24
hours before AI or mating.
BitchAnoestrus
Delayed ovulation, prolonged
pro-oestrus
500 IU IM or IV at first day of
oestrus after pretreatment with
PMSG
20 IU/kg SC daily for 10 days.
100 - 800 IU/day IM, repeating
treatment until vaginal
bleeding
disappears. Mate on
behavioural oestrus.
Male dogDeficiency in libido100 - 500 IU – IM twice weekly
for up to 6 weeks, but if this is
not possible then 100 - 500 IU
IM. 6 - 12 hours before mating
may give a temporary effect.
Further information
The product has been used in cases of cryptorchidism in the dog prior to
castration (100 – 500 IU intramuscularly twice weekly for up to 6 weeks).
Treatment may be effective in some cases provided that the inguinal canal is
patent, and that therapy commences early.
The product has intrinsic LH-like activity. Injection of 1 500 IU 12 days after
heat in cattle enhances the active life of the corpus luteum by 2 to 3 days,
resulting in increased progesterone and suppression of oestradiol production.
These changes are consistent with those observed after GnRH use at
day 11 – 13 of the cycle which are believed to be responsible for the
increased pregnancy rates seen after such use. The mode of action is
however different since the product does not rely on first stimulating an
endogenous LH peak. This use of the product has not been investigated in
the field.

None.

Cattle, horses, dogs:
Rare
(1 to 10 animals / 10 000 animals
treated):
Anaphylaxis
1
May occur shortly after injection, as with all protein preparations. Adrenalin
injection (1:1 000) given intravenously or intramuscularly when symptoms
appear is the standard treatment. The administration of corticosteroids may
also be indicated.
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.

None.

Special precautions for safe use in the target species:
Not applicable.
Special precautions to be taken by the person administering the veterinary
medicinal product to animals:
Care should be taken to avoid accidental self-injection. In case of accidental
self-injection, seek medical advice immediately and show the package leaflet
or the label to the physician.
Wash hands after use.
Special precautions for the protection of the environment:
Not applicable.

interaction
None known.

Storage before reconstitution:
Do not store above 25 °C.
Storage after reconstitution:
Protect from light.
Any veterinary medicinal product not used immediately after reconstitution
should be stored refrigerated between 2 °C and 8 °C. Reconstituted product
remaining 24 hours after preparation should be discarded safely.
This veterinary medicinal product does not contain an antimicrobial
preservative.
Avoid the introduction of contamination during use.

Cattle: Meat and offal – Zero days.
Milk – Zero hours.
Horses: Meat and offal – Zero days.

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.