Welcome to our new website! Change your current password NOW to gain access to your account and all our new features!

Reset Password
  • Account

Pharmacokinetics of Compounded Short- and Long-Acting Progesterone study

Ryan A Ferris DVM, MS, DACT, Brittany A. Palmer, Patrick M McCue DVM, PhD, DACT Equine Reproduction Laboratory, Colorado State University, Fort Collins, CO, USA

 

Exogenous progesterone is commonly administered to support a pregnancy in a mare that has endogenous progesterone levels of 1 or in a hormonally manipulated embryo transfer recipient mare2. The goal of this study was to determine the pharmacokinetics of a short-acting and long-acting compounded progesterone product.

Anestrus mares were administered an intramuscular injection of either 200 mg of short-acting progesterone (n=3) (progesterone in cottonseed oil, 100 mg/mL, Doc Lane Pharmacy Formula, Lexington KY) or 1500 mg of long-acting progesterone (n=3) (progesterone in sesame oil, 150 mg/mL, Doc Lane Pharmacy Formula, Lexington KY). Blood plasma was collected just prior to (Time 0) and selected intervals after administration of both products. Plasma progesterone concentration was determined using a validated ELFA assay (MiniVIDAS®; bioMérieux)3. Data are presented as mean ± standard deviation. The short-acting progesterone group’s mean blood progesterone concentration was 7.7 ± 1.0 ng/ml at 2 hours and 4.7 ± 0.4 ng/ml at 24 hours after administration (Figure 1). The long-acting progesterone treatment had a mean blood progesterone value of 11.3 ± 0.4 ng/ml at 24 hours and 5.6 ± 0.3 ng/ml 7 days post administration (Figure 1). After 14 days of administration the mean blood progesterone value was 0.9 ± 0.1 ng/ml.

In summary, the Doc Lane Short-acting progesterone product maintained blood values above 4 ng/mL for 24 hours and was effectively cleared by 72 hours after administration. In contrast, the Doc Lane Long-acting progesterone product maintained blood values above 4 ng/ml for 7 days, but remained above 1 ng/ml for approximately 14 days following administration.

 

 

References:

  1.  McCuePM.HormoneTherapyinClinicalEquinePractice.VetClinofNAmerica:EqPract.2016;32:425-434.
  2.  Ferris RA and McCue PM. How To Overcome Challenges in An Embryo Transfer Program. Proceedings AAEP 2017San Antonio.
  3.  Glapa KE, Ferris RA, Palmer BD, McCue PM. Comparison Of Blood Progesterone Values Obtained From An In-House One Hour Enzyme Linked Fluorescent (ELFA) With Radioimmunoassay (RIA). Clinical Theriogenology. 2017;9:457.