Aglepristone
Aglepristone is a progesterone-receptor antagonist used to terminate pregnancy in bitches. Selected feline reproductive uses are extralabel.
Successful treatment requires confirmation that pregnancy has ended and the uterus has emptied. It can also be part of selected medical pyometra protocols, which require close reassessment.
Group
Antiprogestin; progesterone-receptor antagonist
Mechanism of Action
Competitive progesterone-receptor antagonism interrupts progesterone-dependent uterine support and promotes pregnancy termination. Antiglucocorticoid activity can reduce glucocorticoid effects.
Dose Rates
Dogs
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Pregnancy termination | 10 mg/kg | SC | Every 24 h | Up to 2 days; Do not use in: Desired ongoing pregnancy, More than 45 days after mating, Hepatic or renal impairment, Diabetes mellitus, Hypoadrenocorticism, Poor general health; Two injections total. Treat after the end of estrus and no later than day 45 after mating. Maximum injection volume is 5 mL per site; confirm uterine evacuation by ultrasound. |
Cats
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Pregnancy termination | 10 mg/kg | SC | Every 24 h | Up to 2 days; Do not use in: Desired ongoing pregnancy, Pregnancy later than the second trimester; Two injections total. Extralabel; do not use later than the second trimester. Some protocols combine misoprostol, which requires a separate regimen. |
| Pyometra | 10 mg/kg | SC | Administer on days 1, 2, 7 and 14; this is not a uniform dosing interval. Monitor uterine response and systemic illness. |
Indications
- Pregnancy termination in bitches up to 45 days after mating.
- Extralabel feline pregnancy termination.
- Selected feline pyometra treatment protocols.
- Reported treatment of progesterone-associated feline mammary hyperplasia; a regimen is not established in this record.
Contraindications
- Do not use to preserve a desired pregnancy.
- For labeled canine pregnancy termination, do not administer beyond day 45 after mating.
- Do not use in dogs with hepatic or renal impairment, diabetes, poor general health, or known/latent hypoadrenocorticism or genetic predisposition to it.
- Hypersensitivity to aglepristone or excipients, including the oily vehicle.
- Accidental self-injection is particularly hazardous during human pregnancy; prevent skin exposure and self-injection.
- Do not administer to food-producing animals.
Interactions
- May antagonize glucocorticoid therapy.
- Potential interactions with ketoconazole, itraconazole and erythromycin have not been adequately characterized.
- Do not mix the injection with other medicines in the same syringe.
Adverse effects
- Injection-site pain, swelling, inflammation or thickening.
- Anorexia, depression, excitation, diarrhea or vomiting.
- Vaginal discharge and mammary congestion accompanying termination.
- Incomplete abortion, uterine infection or treatment failure; failure can lead to dystocia or uterine rupture.
Toxicity
High injection volumes increase local inflammation. After pregnancy termination, persistent pregnancy or retained uterine contents is clinically important even without an overdose. Confirm completion by ultrasound about 10 days after treatment and no earlier than 30 days after mating in bitches.
Preparations
| Preparation | Form | Strength | Route |
|---|---|---|---|
| Alizin 30 mg/mL Oily solution containing refined arachis oil; no antimicrobial preservative. Maximum 5 mL per injection site in large bitches. | Injection | 30 mg / mL | SC |