Zepbound and Oral Contraceptives
Zepbound (tirzepatide) does not require any special precautions or dosage adjustments when used with oral contraceptives, as GLP-1 receptor agonists like tirzepatide are not enzyme inducers or inhibitors that affect contraceptive steroid metabolism. 1
Key Clinical Points
No Clinically Significant Interaction
- Tirzepatide can be used safely and effectively with oral contraceptives without additional contraceptive precautions. 1
- GLP-1 receptor agonists (the drug class to which Zepbound belongs) are not listed in CDC Medical Eligibility Criteria tables of drug interactions with combined oral contraceptives. 1
- Tirzepatide is not classified as a cytochrome P450 enzyme inducer or inhibitor that could affect the metabolism of contraceptive steroids. 1
Drugs That DO Reduce Contraceptive Efficacy (For Comparison)
It's important to distinguish tirzepatide from medications that actually interact with oral contraceptives:
Enzyme-inducing anticonvulsants (Category 3 - risks usually outweigh benefits):
- Phenytoin, carbamazepine, barbiturates, primidone, topiramate, and oxcarbazepine reduce oral contraceptive effectiveness. 2, 1
- These require oral contraceptives with minimum 30 μg ethinyl estradiol or alternative contraceptive methods. 2
Antimicrobial agents:
- Rifampin or rifabutin significantly reduce contraceptive efficacy (Category 3). 2, 1
- Broad-spectrum antibiotics, antifungals, and antiparasitics do NOT significantly interact with oral contraceptives. 2, 1
Ritonavir-boosted protease inhibitors may reduce oral contraceptive efficacy (Category 3). 2, 1
Clinical Recommendations for Zepbound Users
- No additional barrier contraception is needed when taking Zepbound and oral contraceptives simultaneously. 1
- Standard-dose oral contraceptives (including those with <30 μg ethinyl estradiol) remain effective with tirzepatide. 1
- No dosage adjustments of either medication are necessary. 1
Common Pitfall to Avoid
Do not confuse GLP-1 receptor agonists with enzyme-inducing medications. The evidence clearly demonstrates that tirzepatide lacks the metabolic enzyme effects (particularly on CYP3A4, which metabolizes contraceptive steroids) that characterize problematic drug interactions with oral contraceptives. 1