Hormones and Birth Control with thyroid medication (levothyroxine)
Levothyroxine is one of the most prescribed medications worldwide, and many adults on it also use chronic medications such as Hormones and Birth Control (Hormones and Birth Control). The combination is generally safe, but levothyroxine's narrow therapeutic index and finicky absorption mean a few practical points matter more than for most other co-administered drugs at 1%, 1.62%, 0.3mg, 0.625mg, 1.25mg.
How Hormones and Birth Control affects thyroid medication
Levothyroxine absorption is sensitive to timing relative to food, calcium, iron and several medications. Whether Hormones and Birth Control interferes depends on Clomiphene, Conjugated Estrogens, Drospirenone, Estradiol, Estriol, Levonorgestrel, Levothyroxine, Progesterone, Raloxifene, Testosterone, Tibolone — most agents in Hormones and Birth Control have no clinically meaningful effect on thyroid hormone levels, but a small number affect TSH or T4 free fraction. Emergency contraception with levonorgestrel (Plan B) is most effective when taken as soon as possible after unprotected intercourse, ideally within 72 hours.
Practical timing
According to standard endocrine practice, levothyroxine is taken on an empty stomach at least 30 minutes before food and 4 hours from interacting medications. Hormones and Birth Control at 1%, 1.62%, 0.3mg, 0.625mg, 1.25mg can usually be taken at any time relative to the levothyroxine dose, but the prescribing information for Clomiphene, Conjugated Estrogens, Drospirenone, Estradiol, Estriol, Levonorgestrel, Levothyroxine, Progesterone, Raloxifene, Testosterone, Tibolone should be checked for specific timing instructions.
Frequently asked questions
Will Hormones and Birth Control affect my thyroid levels? ▾
Most Hormones and Birth Control medications do not directly affect thyroid hormone levels at 1%, 1.62%, 0.3mg, 0.625mg, 1.25mg. Some affect TSH testing, hormone-binding proteins or T4 free fraction in subtle ways. Routine thyroid function tests every few months catch any meaningful drift.
When should I take Hormones and Birth Control relative to levothyroxine? ▾
Levothyroxine is taken on an empty stomach with at least a 30-minute fast and 4-hour separation from interacting medications. Hormones and Birth Control at 1%, 1.62%, 0.3mg, 0.625mg, 1.25mg usually has no specific timing constraint relative to levothyroxine; the pharmacist confirms based on the prescribing information for Clomiphene, Conjugated Estrogens, Drospirenone, Estradiol, Estriol, Levonorgestrel, Levothyroxine, Progesterone, Raloxifene, Testosterone, Tibolone.
Medications in Hormones and Birth Control
More on Hormones and Birth Control
- With alcoholHormones and Birth Control and alcohol — is it safe to drink?
- With foodShould Hormones and Birth Control be taken with food?
- Side effectsHormones and Birth Control side effects: common, rare and warning signs
- For older adultsHormones and Birth Control after 60: doses and safety in older adults
- For womenHormones and Birth Control for women: indications and considerations
- For menHormones and Birth Control for men: indications and considerations
The information on this website is provided for reference and educational purposes only. It does not replace consultation with a qualified healthcare professional.