Cloprostenol / Dinoprost (PGF2α)

What is this medication for?

• Luteolysis: estrus synchronization, pyometra, endometritis, mummified fetus/fetal maceration; silent-estrus resolution
• Estrus manipulation (short-cycle/breeding scheduling); induction of luteolysis — NOT for pregnant mares unless abortion intended
• Estrus synchronization, abortion induction (per label)
• Pyometra (medical management — largely displaced by aglepristone/surgery)

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

• The double-commandment: confirm NOT pregnant before dosing (unless terminating), and pregnant/asthmatic handlers don't touch the bottle — both are label-level rules.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Uterine contractions/straining, discomfort (Expected pharmacology)
• Bronchospasm (human exposure) (Class effect)
• Hypersalivation/restlessness (dinoprost esp.) (Transient)
• Hypotension/colic-signs transient (Possible)

Worth a phone call to your veterinarian

• Any new symptom that worries you.

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Trouble breathing, collapse, seizures, severe vomiting or diarrhea, facial swelling, or pale gums

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: Pregnant animals (unless termination intended); handlers pregnant/asthmatic
• has or has had: Closed-cervix pyometra (bitch — uterine rupture theoretical); stress-compromised animals

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • Progestins (altrenogest)
  • Oxytocin
  • NSAIDs (PG-synthesis inhibitors)

Storage and handling

Refrigeration per label; PREGNANT/NURSING WOMEN + ASTHMATICS SHOULD NOT HANDLE (absorption + breathing difficulty/airway tightening + uterine contraction) — the glove-and-caution dispensing class.

Good to know

• The double-commandment: confirm NOT pregnant before dosing (unless terminating), and pregnant/asthmatic handlers don't touch the bottle — both are label-level rules.
• Synchronization arithmetic (2 shots × 11 days) exists because of CL-age sensitivity — days 5–17 responsive, otherwise you paid for a placebo.
• Cloprostenol-vs-dinoprost: same destination (luteolysis), different potency/units — micrograms vs mg discipline like the α2 family.