Definition: A progestin is a hormone that acts like progesterone. Menopause hormone labels pair one with estrogen for a woman with a uterus, because they say estrogen alone raises the risk of endometrial cancer. Prempro, Activella and Angeliq each combine estrogen with a different progestin in one tablet.
| Product | Estrogen | Progestin |
|---|---|---|
| Prempro / Premphase | Conjugated estrogens | Medroxyprogesterone acetate (MPA) |
| Activella | Estradiol | Norethindrone acetate |
| Angeliq | Estradiol | Drospirenone |
Progesterone itself (Prometrium, and in Bijuva) is used for the same purpose. The endometrial hyperplasia page has the trial numbers those labels report.
Prempro, Activella and Angeliq carry the full estrogen plus progestin boxed warning. It draws on the Women's Health Initiative, which tested conjugated estrogens with MPA and found higher risks of pulmonary embolism, deep vein clots, stroke and heart attack. The labels say estrogens, with or without progestins, are prescribed at the lowest effective dose for the shortest time that meets treatment goals.
Progestins differ. The Angeliq label says drospirenone has antialdosterone activity, which can raise potassium, so the label adds a high-potassium warning.
Some schedules give the progestin every day and others only on certain days, as with Premphase. Logging which product you take and each dose, plus any bleeding days, shows your prescriber whether the plan is being followed.
Read more on Dose Track: Prempro side effects · Activella side effects · Angeliq side effects · Prempro vs Activella