Can you donate blood if you take levothyroxine?
Yes in general. People who take levothyroxine (Synthroid, Levoxyl) can donate if their thyroid condition is controlled and they feel well.
Levothyroxine (Synthroid, Levoxyl, Euthyrox) is the standard treatment for an underactive thyroid. It replaces a hormone your body would normally make, and it generally does not stop you from donating blood.
To be accepted
- Your thyroid condition should be controlled, with your lab results in range
- You should have no symptoms of hypothyroidism on the day, like extreme fatigue or a very slow pulse
- You should not take other medications that would defer you
Why it is usually accepted
Levothyroxine does not suppress the immune system, does not increase infection risk through blood and does not affect the quality of blood components.
When there might be an issue
- Uncontrolled hypothyroidism with symptoms
- Hypothyroidism after thyroid cancer treated with radioactive iodine: specific rules may apply
- Use together with steroids or immunosuppressants for another condition
Tip
Bring a list of your medications and, if you have it, a recent TSH result. The screener will assess you on the day.
This information is general and does not replace advice from a health professional. Your eligibility is always decided at the donor screening on the day of donation. Rules change, so confirm with the American Red Cross or the blood center where you plan to donate.