Hydroxyprogesterone Caproate Side Effects

Common Reactions

Hydroxyprogesterone caproate has been studied thoroughly in clinical trials. In these studies, one group of women received hydroxyprogesterone caproate, while another group was given a placebo (an injection with no active ingredients). As a result, it was possible to see what side effects occurred, how often they appeared, and how they compared to the placebo.
In clinical trials, the most common side effects of hydroxyprogesterone caproate included:
  • Pain at the injection site -- in up to 34.8 percent of women
  • Swelling at the injection site -- up to 17.1 percent
  • Hospital admission for preterm labor not resulting in preterm birth -- up to 16 percent
  • Hives -- up to 12.3 percent
  • Preeclampsia or high blood pressure -- up to 8.8 percent
  • General itching -- up to 7.7 percent.
Other common problems (occurring in 2 to 6 percent of people) included:
Some of these common reactions could also be classified as serious side effects. In addition, hydroxyprogesterone caproate appeared to slightly increase the risk of miscarriages and very slightly increase the risk of stillbirth, but it is unclear if the small differences are statistically significant or not.

Final Thoughts

You may experience some or none of the hydroxyprogesterone caproate side effects listed in this article. Unfortunately, there is no way for your healthcare provider to know beforehand if you will have problems with a medicine that you have never tried.
Therefore, make sure to let your healthcare provider know if you develop any adverse reactions while receiving the drug or if something "just does not seem right." While it may not be a side effect of hydroxyprogesterone caproate, your healthcare provider will be able to diagnose and treat the problem.
Last reviewed by: Kristi Monson, PharmD
5 Common Relationship Mistakes for Adults With ADHD