Dinoprost

Major Uses

Dinoprost is a prostaglandin typically used in cattle as a luteolytic agent. By causing luteolysis (the degeneration of ovarian luteinized tissue) the drug can control and synchronize heat cycles in mares and cattle. The drug is also used in small animals for the treatment of pyometra, which is a common uterine infection. Dinoprost can be used to induce abortions as well.

Common Precautions

Many adverse reactions can occur with the use of dinoprost, especially in dogs and cats. Reactions may include diarrhea, abdominal pain, urination, vomiting, increased heart and respiratory rates, and bronchoconstriction. Salivation, panting, incoordination, anxiety, and restlessness are additional signs of adverse reactions. Typically these reactions occur minutes after administration of the drug and can persist for about 20 - 30 minutes. Dinoprost should never be administered to any pregnant animals, unless it is being used specifically to induce abortion. The drug should not be given to animals with respiratory diseases, like asthma, and to mares with disorders of the vascular system, gastrointestinal and reproductive tracts. Dinoprost should be used with extreme caution in dogs and cats that are older than eight years of age, and those that have any serious diseases of the heart, liver and kidneys.

Possible drug interactions can occur, so the prescribing veterinarian should be informed of all other medications the pet is taking prior to administration of dinoprost. For example, the drug can interact with other oxytocic agents and enhance activity.

Dinoprost should not be administered to animals with a known allergy or hypersensitivity to the drug. Because dogs seem to be more susceptible to the toxic effects, the pet's veterinarian or emergency care should be sought immediately if any unusual reactions occur.

Storage

Dinoprost injectable should be kept in airtight containers at room temperature; the drug is not particularly sensitive to heat or light.

Administration

Dinoprost is only available in the injectable form in 10 mL and 30 mL vials of 5 mg/mL of dinoprost. For the treatment of pyometra, the dose for dogs is 0.1 - 0.2 mg/kg and for cats the dose is 0.1 - 0.25 mg/kg, both should be administered every 24 hours subcutaneously for five days. For horses for estrous synchronization, the typical dose is 1 mg/100 lb (1 mg/45 kg) intramuscularly once. Dinoprost should never be injected intravenously to any animal. Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.