Cloprostenol

Products

Cloprostenol is commercially available as a solution for injection. It has been approved in many countries since 1977 and exclusively as a veterinary drug.

Structure and properties

Cloprostenol (C22H29ClO6, Mr = 424.9 g/mol) is a synthetic analog of prostaglandin F2α and structurally related to it. It exists as a white powder and is highly soluble in water. Cloprostenol is a racemic mixture. Only the dextrorotatory enantiomer (+)-cloprostenol is biologically active. It has a 3.5-fold higher potency than the racemate because it has a much higher specific binding affinity for the prostaglandin F2α receptors in the cell membranes of the corpus luteum. Therefore, many preparations contain only the dextrorotatory enantiomer.

Effects

Cloprostenol (ATCvet QG02AD90) has a luteolytic effect. It dissolves the corpus luteum and causes it to recede rapidly. This leads to a rapid drop in progesterone levels. The subsequent increased release of follicle-stimulating hormone (FSH) induces the maturation of a follicle, leading to oestrus with subsequent ovulation. Furthermore, cloprostenol stimulates the smooth muscles of the uterus, digestive tract, respiratory tract and blood vessels. The luteolytic effect depends on the species and timing of treatment, but sets in within 2-5 days.

Indications

In cattle, horses, pigs, sheep, and goats:

  • Oestrus synchronization
  • Oestrus, birth and abortion induction.
  • Interruption of a pregnancy
  • Expulsion of mummified fetuses and pathological secretions from the uterus.
  • Dysfunction of the ovaries
  • Endometritis (inflammation of the endometrium).
  • Pyometra (purulent inflammation of the uterus).
  • Cysts, existing corpus luteum and in delayed involution of the uterus.

Dosage

According to the SmPC. Cloprostenol is administered intramuscularly.

Contraindications

Cloprostenol is contraindicated in hypersensitivity, respiratory and cardiovascular disease, spastic respiratory and digestive diseases. Cloprostenol should not be used in pregnant animals in which induction of parturition or abortion is not desired. F2α-type prostaglandins may be absorbed through the skin and cause miscarriage and bronchospasm. For this reason, pregnant women, women of childbearing age, and persons with asthma or other respiratory diseases should avoid contact with cloprostenol or wear gloves when using it (e.g., veterinarians!). For complete precautions, see the drug label.

Interactions

Cloprostenol should not be used with nonsteroidal anti-inflammatory drugs because they inhibit endogenous prostaglandin synthesis. Cloprostenol may potentiate the activity of other oxytocic agents.

Adverse effects

Possible adverse effects include sweating, increased body temperature, increase in respiratory and heart rates, increased salivation, increased defecation and urination, skin reactions, pruritus, dysmotion, dyspnea, spasm of abdominal muscles, and changes in nestling behavior. In cattle, delayed postpartum discharge should be expected after induction of labor with cloprostenol. Side effects depend on the animal species.