Can Mounjaro Make Birth Control Less Effective?

Millions of people are currently taking glucagon-like peptide-1 (GLP-1) medications, like Mounjaro, to lose weight or treat diabetes. However, it’s essential to understand any potential drug interactions, including with birth control. The US Food and Drug Administration (FDA) warns that Mounjaro may impact the effectiveness of oral contraceptives, potentially resulting in unintended pregnancy.

Keep reading to understand the potential risks of combining Mounjaro with oral contraceptives, along with suggested alternatives.

How Mounjaro Works

Mounjaro (tirzepatide) is a dual agonist, meaning that the drug targets the cell receptors of two hormones involved in blood sugar regulation: glucagon-like peptide-1 and glucose-dependent insulinotropic polypeptide. By activating both receptors, Mounjaro enhances their function, helping to maintain stable blood glucose levels in individuals with diabetes.

The drug helps people feel fuller by slowing down digestion by a process known as delayed gastric emptying. This effect might impact the absorption of certain oral medications, such as birth control pills, that depend on the gastrointestinal tract for proper absorption.

Impact of Mounjaro on Birth Control

The FDA recommends that individuals taking birth control pills should consider another form of birth control for four weeks after starting Mounjaro, as well as for four weeks after each dose increase.

While more research is needed to fully understand how Mounjaro might reduce the effectiveness of oral contraceptives, many theorize it impacts their absorption, says Courtney Younglove, M.D., a dual board-certified physician specializing in Obesity Medicine and Obstetrics & Gynecology.

Because so much is still unknown — including whether progestin-only pills are affected differently than combined oral contraceptives — Dr. Younglove recommends using a backup method of contraception while taking Mounjaro, particularly when starting or increasing the dose.

Alternative Contraceptive Options

While Mounjaro may lessen the effect of oral birth control pills, this issue doesn’t apply to non-oral contraception. If you’re starting Mounjaro, Dr. Younglove recommends opting for physical contraceptives, such as an intrauterine device (IUD), condoms, a contraceptive patch or a vaginal ring. Or, if you prefer staying on the birth control pill, she suggests using condoms as well.

Dr. Younglove emphasizes the importance of using a backup form of birth control while taking Mounjaro, regardless of the chosen method. Given the unknown effects of these drugs on a developing fetus, it’s important to minimize any potential risk.

Check out two more articles in our interaction series: Can I Take Melatonin with Ambien? and Can I Take Tums with Metoprolol?