# Cloprostenol: veterinary dose and monograph

> Cloprostenol is a veterinary drug. Synthetic PGF2α analogue — luteolytic. Indications include corpus luteum regression; chronic endometritis / pyometra (post-pus-removal); oestrus synchronisation. This monograph lists 9 reference doses for dogs, cattle, horses, goats, pigs and buffalo, each with route, frequency and source, plus meat and milk withdrawal periods for food animals.

Source: https://vetmasterji.com/drugs/cloprostenol · Last reviewed: 2026-10-01

## At a glance

- **Drug class:** Veterinary drug
- **Also known as:** Pragma, Estrumate, Pregova
- **Species with doses:** Dogs, Cattle, Horses, Goats, Pigs and Buffalo
- **Routes:** IM, SC
- **Last reviewed:** 1 October 2026

## Indications

- Corpus luteum regression
- Chronic endometritis / pyometra (post-pus-removal)
- Oestrus synchronisation
- Induction of parturition (cattle, sows)
- Termination of pregnancy / removal of mummified foetus
- Persistent CL / luteal cyst / COD

## Cloprostenol dose by species

Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them.

### Dogs

*Cloprostenol doses for dogs*

| Indication | Dose | Route | Frequency | Duration |
| --- | --- | --- | --- | --- |
| Open-cervix pyometra (adjunct) | 1–5 µg/kg SC once daily | SC | q24h (up to 2–3 weeks) | — |
| Pregnancy termination (after day 25–30) | 1–2.5 µg/kg SC once daily | SC | q24h for 4–7 days | — |

- Open-cervix pyometra (adjunct): Plumb’s p.305 (Romagnoli 2002): 1–5 µg/kg once daily, starting at half the dose and reaching the full dose over 2–3 days; may need 2–3 weeks. Alternative: 1 µg/kg SC every 5 days with aglepristone 10 mg/kg SC every 5 days (Threlfall 2006). Open cervix only.
- Pregnancy termination (after day 25–30): Papich 5e: 1–2.5 µg/kg SC once daily for 4–5 days from day 25 after mating (fewer side effects at 1 µg/kg). Plumb’s p.305 (Davidson 2004): 1–2.5 µg/kg SC daily for 4–7 days after 30 days of gestation; atropine 15 min before reduces adverse effects.

### Cattle

*Cloprostenol doses for cattle*

| Indication | Dose | Route | Frequency | Duration | Withdrawal |
| --- | --- | --- | --- | --- | --- |
| CL regression / synchronisation | 500 µg per cow IM (2 mL) | IM | once (Day 0; AI 48–72 h later) | — | no slaughter withdrawal / no milk discard |
| Pyometra (after pus drainage) | 500 µg per cow IM | IM | once, may repeat 11 days later | — | Withdrawal NOT established — treat as extra-label |
| Induction of parturition (>270 d gestation) | 500 µg per cow IM | IM | once | — | Withdrawal NOT established — treat as extra-label |

- CL regression / synchronisation: 500 µg (2 mL) per cow IM. WITHDRAWAL — Plumb's p.306 (Estrumate / estroPLAN): FDA-approved for beef and dairy cattle; NO preslaughter withdrawal and NO milk withdrawal is required, and no specific residue tolerances have been set.
- Pyometra (after pus drainage): Plumb’s p.305: pyometra or chronic endometritis 500 µg IM (up to 97% efficacy; McCormack; Estrumate label); also for mummified fetus and luteal cysts. Papich 5e: 500 µg IM, repeatable 11 days later. Never give to pregnant animals unless termination is intended.
- Induction of parturition (>270 d gestation): Label-sourced (some national Estrumate labels): 500 µg IM from day 270; calving usually follows in 2–3 days and retained placenta is common. Plumb’s 10e p.300 lists 500 µg/cow IM for induced abortion, oestrus problems and synchronisation but gives no cattle parturition-induction regimen, and neither does Papich 5e.

### Horses

*Cloprostenol doses for horses*

| Indication | Dose | Route | Frequency | Duration |
| --- | --- | --- | --- | --- |
| CL regression / mummified foetus | ≤400 kg: 125–250 µg IM; >400 kg: 250–500 µg IM | IM | once | — |

- CL regression / mummified foetus: Plumb’s p.305: luteolysis 250 µg IM once — one-tenth of that dose still causes luteolysis with fewer side effects (Dascanio); 25–250 µg IM once, not more than 1 day after ovulation (Foss); abortion before day 12: 100 µg IM. Papich 5e: 500 µg IM to terminate pregnancy; endometritis 250 µg IM twice 12 h apart. The weight-banded 125–500 µg label range is from product labelling. Sweating and colic-like signs are common.

### Goats

*Cloprostenol doses for goats*

| Indication | Dose | Route | Frequency | Duration | Withdrawal |
| --- | --- | --- | --- | --- | --- |
| Induction of parturition (day 144) | 62.5–125 µg/doe | IM | once, early morning | — | Withdrawal NOT established — treat as extra-label |

- Induction of parturition (day 144): Plumb’s p.305 (Williams 1986): 62.5–125 µg IM at 144 days of gestation, in the early morning; deliveries peak 30–35 h later. Pseudopregnancy (hydrometra/mucometra): 125 µg IM once (Tibary 2009).

### Pigs

*Cloprostenol doses for pigs*

| Indication | Dose | Route | Frequency | Duration | Withdrawal |
| --- | --- | --- | --- | --- | --- |
| Induction of farrowing (sow, day 113+) | 175 µg per sow IM, no earlier than 2 days before the expected farrowing date | IM | once | — | no slaughter withdrawal |

- Induction of farrowing (sow, day 113+): Plumb’s p.305 (Pugh 1982): 175 µg IM given 2 days or less before the anticipated farrowing date; farrowing generally occurs about 36 h later. Earlier use gives weak piglets.

### Buffalo

*Cloprostenol doses for buffalo*

| Indication | Dose | Route | Frequency | Duration | Withdrawal |
| --- | --- | --- | --- | --- | --- |
| Oestrus synchronisation / CL regression / pyometra | 500 µg per buffalo IM (2 mL) | IM | once (repeat 11 d for synch) | — | Withdrawal NOT established — treat as extra-label |

- Oestrus synchronisation / CL regression / pyometra: Intas/MSD catalogues label buffalo with cattle: 500 µg (2 mL) IM. Buffalo are seasonally anoestrous — often combined with GnRH (Ovsynch/Double-Ovsynch). Never use in pregnant buffalo (abortifacient).

## Contraindications

Pregnant animals (induces abortion / parturition). Asthma in human handlers — pregnant women must not handle product. Hypersensitivity.

## Species-specific warnings

> **Caution:** Horses: Cloprostenol can cause sweating, mild colic, dyspnoea in mares — these are transient.

## Adverse effects

- Transient sweating / dyspnoea / abdominal discomfort (rare in cattle)
- Local injection-site reaction
- Premature parturition / abortion if used in pregnant animals

## Drug interactions

- GnRH (buserelin): SEQUENTIAL synergy in ovsynch — GnRH day 0 → cloprostenol day 7 → GnRH day 9 → AI day 10
- Oxytocin: synergistic uterine contraction — used together for retained placenta
- Tocolytics (clenbuterol): ANTAGONISE cloprostenol uterine effect — avoid in dystocia management
- NSAIDs: theoretical blunting of PGF2α effect (NSAIDs inhibit endogenous PG synthesis) — usually clinically irrelevant at single-dose use
- Corticosteroids: synergistic for induction of parturition / abortion

## Pregnancy and lactation

ABORTIFACIENT in early pregnancy (before maternal recognition / luteolysis sensitivity changes) — used INTENTIONALLY for abortion / pregnancy termination in cattle. AVOID accidental exposure in pregnant cattle if pregnancy is desired. PROHIBITED FOR HUMAN HANDLING IN PREGNANCY — absorbed through human skin and can cause abortion / bronchospasm in pregnant women / asthmatic handlers. ALL HANDLERS MUST WEAR GLOVES.

## Monitoring

- HANDLER SAFETY: gloves mandatory; pregnant or asthmatic personnel must NOT handle
- Pregnancy status DOCUMENTED before every administration (in cattle) — abortifacient
- Oestrus detection 48–72 h post-injection
- Withdrawal: 0 d milk / 1 d slaughter (Indian cattle label — verify per jurisdiction)
- Mare colic / sweating signs at 30–60 min — usually transient
- Retained placenta cows: re-evaluate uterine evacuation at 12–24 h

## Toxicity and overdose

HUMAN HANDLER RISK: absorbs through skin. Pregnant women: abortion risk from skin exposure. Asthmatic handlers: severe bronchospasm. ALWAYS WEAR GLOVES — accidental self-injection requires immediate medical attention. Cattle: transient sweating, mild colic, increased respiratory rate (resolves in 1–2 h). Horses: more dramatic — sweating, abdominal pain, colic, dyspnoea — but transient. Goats / sheep: similar to cattle. Pigs: salivation, vomiting at high doses.

Management: No specific antidote. Supportive: anti-spasmodic for severe colic (hyoscine butylbromide 0.3 mg/kg slow IV), bronchodilator (terbutaline / clenbuterol) for bronchospasm. Most effects self-limiting within 1–2 h. Human exposure: WASH SKIN immediately, seek medical attention if pregnant or asthmatic. Bronchospasm: nebulised beta-2 agonist.

## Clinical pearls

- OVSYNCH PROTOCOL: GnRH (buserelin 10 µg) day 0 → cloprostenol 500 µg day 7 → GnRH day 9 → timed AI day 10
- Bovine pyometra: 500 µg IM, repeat 11 days later if needed — combine with antibiotic therapy
- Bovine retained placenta (>24 h): 500 µg IM + oxytocin — uterine evacuation
- Bovine induction of parturition (>270 d gestation): 500 µg IM (within 24–72 h of calving)
- Equine CL regression / mummified foetus: 125–500 µg IM depending on weight
- Porcine farrowing induction (day 113+): 175–250 µg IM
- HANDLERS MUST WEAR GLOVES — skin absorption can cause abortion in pregnant women, bronchospasm in asthmatics
- NEVER use in pregnant women / asthmatic personnel — accidental exposure can be dangerous
- Transient sweating / mild colic in cattle / horses post-injection — explain to client as normal
- Zero milk withdrawal — convenient for all stages of dairy production

## Mechanism of action

Synthetic prostaglandin F2α analogue — ~100× more potent than natural PGF2α and resistant to enzymatic degradation. Binds PGF2α (FP) receptors on the corpus luteum (CL) → causes luteolysis (CL regression) within 24–48 h → drop in progesterone → return to oestrus or expulsion of uterine contents. Also stimulates myometrial contraction (uterine evacuation). Standard ecbolic + luteolytic in dairy / beef reproductive practice.

## Formulations and products

- Pragma 250 µg/mL (Intas, 2 / 10 mL)
- Estrumate 250 µg/mL (MSD, 2 mL ampoule)
- Pregova 250 µg/mL (Virbac)
- Pragma (Intas (Neovet)) — 250 µg/mL, Injection
- Estrumate (MSD Animal Health) — 250 µg/mL, Injection
- Pregova (Virbac) — 250 µg/mL, Injection
- Repregna (Mankind Veticura) — 250 µg/mL, Injection
- Clopcure (Assure Biotech, Jagadhri (HR)) — Cloprostenol sodium 263 mcg eq. cloprostenol 250 mcg per mL, Injection - IM

## Storage

Injection: 15–25 °C, protect from light. Multidose vial: 28 days after broaching. Do NOT freeze. Wear gloves at all times during handling.

## Before you use this dose

> **Caution:** Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision.

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## Frequently asked questions

### What is the dose of Cloprostenol for dogs?

Reference doses for Cloprostenol in dogs: 1–5 µg/kg SC once daily SC q24h (up to 2–3 weeks) (Open-cervix pyometra (adjunct)); 1–2.5 µg/kg SC once daily SC q24h for 4–7 days (Pregnancy termination (after day 25–30)). Confirm against the label and the patient before use.

### What is the dose of Cloprostenol for cattle?

Reference doses for Cloprostenol in cattle: 500 µg per cow IM (2 mL) IM once (Day 0; AI 48–72 h later) (CL regression / synchronisation); 500 µg per cow IM IM once, may repeat 11 days later (Pyometra (after pus drainage)); 500 µg per cow IM IM once (Induction of parturition (>270 d gestation)). Confirm against the label and the patient before use.

### What is the dose of Cloprostenol for horses?

Reference doses for Cloprostenol in horses: ≤400 kg: 125–250 µg IM; >400 kg: 250–500 µg IM IM once (CL regression / mummified foetus). Confirm against the label and the patient before use.

### What is the withdrawal period for Cloprostenol?

Cattle, IM (CL regression / synchronisation): no slaughter withdrawal / no milk discard; Cattle, IM (Pyometra (after pus drainage)): Withdrawal NOT established — treat as extra-label; Cattle, IM (Induction of parturition (>270 d gestation)): Withdrawal NOT established — treat as extra-label; Goats, IM (Induction of parturition (day 144)): Withdrawal NOT established — treat as extra-label; Pigs, IM (Induction of farrowing (sow, day 113+)): no slaughter withdrawal; Buffalo, IM (Oestrus synchronisation / CL regression / pyometra): Withdrawal NOT established — treat as extra-label. Follow the product label and national regulations where they differ.

### When should Cloprostenol not be used?

Pregnant animals (induces abortion / parturition). Asthma in human handlers — pregnant women must not handle product. Hypersensitivity.

### What are the side effects of Cloprostenol in animals?

Transient sweating / dyspnoea / abdominal discomfort (rare in cattle); Local injection-site reaction; Premature parturition / abortion if used in pregnant animals.

## Sources

- Intas Animal Health catalogue · Pragma
- MSD Animal Health catalogue · Estrumate
- Plumb's Veterinary Drug Handbook
- Papich, Papich Handbook of Veterinary Drugs, 5th edition

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VetMasterJi is a clinical decision-support and education platform for veterinary professionals and students. It does not provide veterinary advice, diagnosis or treatment for specific animals. All drug doses, calculators and differentials are references that must be independently verified before clinical use; the attending registered veterinarian remains solely responsible for every clinical decision.