What is the Difference Between Misoprostol and Mifepristone?

Misoprostol and Mifepristone are two drugs used in combination for early medical abortion. They have different effects on the body and are used at different stages of the abortion process. Here are the key differences between the two:

1. Function: Mifepristone is a progesterone receptor antagonist that causes decidual necrosis and uterine contractions, while Misoprostol is a prostaglandin E1 analogue that induces uterine contractions and expels the pregnancy tissue.
2. Administration: Mifepristone is typically taken first, followed by Misoprostol one to two days later.
3. Effectiveness: A combination of Mifepristone and Misoprostol is significantly more effective than using Misoprostol alone for early medical abortion. Complete abortion occurred for 96.5% of those given Mifepristone and Misoprostol compared to 76.2% for Misoprostol only.
4. Side Effects: Mifepristone is generally well tolerated, with the most common adverse effect being nausea. Misoprostol causes strong uterine cramping and often heavy bleeding with blood clots. Diarrhea is also reported as a side effect for Misoprostol-only users.

In summary, Mifepristone and Misoprostol are used together for early medical abortion, with Mifepristone blocking the hormone progesterone and Misoprostol causing the uterus to contract and empty. The combination of these two drugs is more effective than using Misoprostol alone, although both drugs can cause side effects such as nausea, cramping, and bleeding.

Comparative Table: Misoprostol vs Mifepristone

Here is a table comparing the differences between Misoprostol and Mifepristone:

Misoprostol and Mifepristone are often used together for medical abortion in the first trimester of pregnancy. The combination of the two drugs has been shown to be more effective and have a shorter induction abortion interval compared to when they are used individually.