Cloprostenol
Cloprostenol is a potent luteolytic prostaglandin analogue used for reproductive management.
Group
Prostaglandin F2alpha analogue
Mechanism of Action
Induces corpus-luteum regression, progesterone decline and uterine contraction.
Dose Rates
Dogs
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Pregnancy termination | 1–2.5 mcg/kg | SC | Every 24 h | Up to 5 days; Begin around day 25 after mating; course 4–5 days. Adverse effects are lower at 1 mcg/kg. |
| Pregnancy termination with cabergoline | Reference only | SC | 35–45 days after mating: cloprostenol 1 mcg/kg SC on days 1 and 3 plus cabergoline 5 mcg/kg orally daily on days 1–7. Preserve the complete combination schedule. | |
| Pregnancy termination with bromocriptine | Reference only | SC | Cloprostenol 1 mcg/kg SC every 48 hours with the staged bromocriptine regimen; see Monitoring and Administration. | |
| Open-cervix pyometra adjunct | Reference only | PO | 1–5 mcg/kg once daily for up to 2–3 weeks, starting at half dose and increasing over 2–3 days; route is not specified. Do not infer a complete medical-pyometra protocol from this bullet. | |
| Pyometra combination treatment | Reference only | SC | Cloprostenol 1 mcg/kg SC every five days for up to 15 days, with aglepristone 10 mg/kg SC every five days until resolved, appropriate antibacterial therapy and hydration. Use only a selected medical-management plan with reassessment. | |
| Pregnancy termination | 1–2.5 mcg/kg | SC | Every 24 h | Up to 7 days; Historical course 4–7 days after approximately day 30 of gestation; confirm completion. |
| Alternate-day pregnancy termination | 1–2.5 mcg/kg | SC | Every 48 h | Three doses total. The supplemental parenthesis says mg/kg but conflicts with the same bullet’s mcg/kg regimen; the thousand-fold unit error is not used. |
Cats
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Pregnancy termination | 5 mcg/kg | SC | Every 24 h | Up to 3 days |
Cattle
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Luteolysis and estrus synchronization | 500 mcg/animal | IM | Once | May repeat 11 days later; estrus generally follows within 2–5 days after the effective injection. |
| Pyometra or chronic endometritis | 500 mcg/animal | IM | Once | For pregnancy termination the described period is one week after mating to about day 150. A mummified fetus may need assistance for removal. |
| Luteal cyst or mummified fetus | 500 mcg/animal | IM | Once | For pregnancy termination the described period is one week after mating to about day 150. A mummified fetus may need assistance for removal. |
| Pregnancy termination | 500 mcg/animal | IM | Once | For pregnancy termination the described period is one week after mating to about day 150. A mummified fetus may need assistance for removal. |
Horses
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Pregnancy termination | 500 mcg/animal | IM | Repeat injections at 12-hour intervals have been used in selected circumstances. | |
| Endometritis | 250 mcg/animal | IM | Every 12 h | Up to 1 days; Two injections 12 hours apart; usually combined with oxytocin. |
| Early pregnancy termination | 100 mcg/animal | IM | Once | Before day 12 of gestation, with greatest described effect around day 7–8 after estrus. |
| Luteolysis | 25–250 mcg/animal | IM | Once | |
| Uterine evacuation | 250 mcg/animal | IM | Every 24 h | Avoid use more than one day after ovulation when preservation of luteal function is desired. |
Pigs
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Parturition induction | 175 mcg/animal | IM | Once | Sows only, no earlier than two days before expected farrowing; parturition generally follows around 36 hours later. |
Goats
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Parturition induction | 62.5–125 mcg/animal | IM | Once | Does around gestation day 144; deliveries commonly peak 30–35 hours afterward. Keep surroundings quiet. |
| Hydrometra or pseudopregnancy | 125 mcg/animal | IM | Once |
Alpacas
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Luteolysis | 100 mcg/animal | IM | Once | Historical restriction: not more than four days after ovulation; pregnancy loss is possible. |
Llamas
| Use / stage | Dose | Route | Schedule | Instructions |
|---|---|---|---|---|
| Luteolysis | 250 mcg/animal | IM | Once | Historical restriction: not more than four days after ovulation; pregnancy loss is possible. |
Indications
- Estrus synchronization
- Pregnancy termination
- Persistent luteal activity
- Selected pyometra or endometritis management
Contraindications
- Pregnancy when continued gestation is intended.
- Handle with particular care around people with asthma or who may be pregnant.
- Do not administer intravenously.
Interactions
- Combination protocols with dopamine agonists or gonadorelin require their full schedules.
- Other uterotonics, including oxytocin, can have enhanced effects.
Adverse effects
- Abortion
- Vomiting, panting, nausea or diarrhea
- Vulvar discharge
- Transient mammary enlargement
- Endometritis after some treatments
Preparations
| Preparation | Form | Strength | Route |
|---|---|---|---|
| Cloprostenol injection 250 mcg/mL Cloprostenol active-equivalent strength; dilute carefully for small-animal use. Do not confuse with more potent dexcloprostenol products. | Injection | 250 mcg / mL | IM, SC |
Monitoring and Administration
Monitor reproductive response, persistent discharge and progesterone when indicated. Human skin exposure can cause bronchospasm or abortion; wash splashes immediately and avoid direct handling exposure.
Dogs are commonly treated at least 8 hours after food to limit vomiting. Dilute accurately for small animals.
Canine combination after 35–45 days post-mating: cloprostenol 1 mcg/kg SC on treatment days 1 and 3, after tenfold saline dilution, plus cabergoline 5 mcg/kg orally daily on days 1–7. A separate bromocriptine protocol uses cloprostenol 1 mcg/kg SC every 48 hours with staged oral bromocriptine.
Dairy synchronization protocol: gonadorelin 86 mcg IM on day 0, cloprostenol 500 mcg IM 6–8 days later, another gonadorelin 86 mcg 30–72 hours later, then insemination 8–24 hours afterward.
Equine premature labor in the final 2–4 weeks is described using two doses 30 minutes apart, but the specific dose for that procedure is not independently stated. Do not infer it from pregnancy-termination dosing.
For a cattle single- or double-injection breeding plan, confirm normal cyclicity, a responsive corpus luteum and absence of unintended pregnancy. Estrus generally follows 2–5 days after the effective injection; insemination timing must be matched to the chosen breeding protocol.
The supplemental canine dose parenthesis of 2.5 mg/kg is inconsistent with its 1–2.5 mcg/kg instruction and is not reproduced as a clinical dose.