Lutalyse and Synchrocept are name brands for dinoprost which is also known as dinoprost trometamol or prostaglandin F 2alpha tromethamine. Prostaglandin F 2-alpha has several pharmacologic effects on the female reproductive system, including stimulation of myometrial activity, relaxation of the cervix, inhibition of steroidogenesis by corpora lutea, and can potentially lyse corpora lutea. In horses it is used clinically to:

• To terminate diestrus and bring a mare back into heat.
• Abort an embryo before day 35 of pregnancy or a ferus up to around day 100.
• To terminate a persistent corpus luteum (false pregnancy).

This article is about the contraindications, toxic effects, dosages, and association drug rules that apply to this medication.

Unless being used as an abortifacient or parturition inducer, dinoprost should not be used during pregnancy in all species. May see decreased efficacy as an abortifacient with progesterone therapy. Dinoprost is contraindicated in animals with bronchoconstrictive respiratory disease (COPD). It should not be administered intravenously. According to the manufacturer, dinoprost is contraindicated in mares with acute or subacute disorders of the vascular system, GI tract, respiratory system or reproductive tract.