Phosphodiesterase type 5 (PDE5) inhibitor
Avanafil with thyroid medication (levothyroxine)
Levothyroxine is one of the most prescribed medications worldwide, and many adults on it also use chronic medications such as Avanafil (Avanafil). 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 50mg, 100mg, 200mg.
How Avanafil affects thyroid medication
Levothyroxine absorption is sensitive to timing relative to food, calcium, iron and several medications. Whether Avanafil interferes depends on Avanafil — most agents in Phosphodiesterase type 5 (PDE5) inhibitor have no clinically meaningful effect on thyroid hormone levels, but a small number affect TSH or T4 free fraction. Avanafil selectively inhibits phosphodiesterase type 5 (PDE5) in the corpus cavernosum, increasing cGMP and enhancing nitric-oxide-mediated vasodilation in response to sexual stimulation.
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. Avanafil at 50mg, 100mg, 200mg can usually be taken at any time relative to the levothyroxine dose, but the prescribing information for Avanafil should be checked for specific timing instructions.
Frequently asked questions
Will Avanafil affect my thyroid levels? ▾
Most Phosphodiesterase type 5 (PDE5) inhibitor medications do not directly affect thyroid hormone levels at 50mg, 100mg, 200mg. 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 Avanafil relative to levothyroxine? ▾
Levothyroxine is taken on an empty stomach with at least a 30-minute fast and 4-hour separation from interacting medications. Avanafil at 50mg, 100mg, 200mg usually has no specific timing constraint relative to levothyroxine; the pharmacist confirms based on the prescribing information for Avanafil.
Products containing Avanafil
More on Avanafil
- With alcoholAvanafil and alcohol — is it safe to drink?
- With foodShould Avanafil be taken with food?
- Side effectsAvanafil side effects: common, rare and warning signs
- Dosage guideAvanafil dosage guide: how much to take and when
- OnsetHow fast does Avanafil start working?
- DurationHow long does Avanafil last?
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