Q. Can Synthroid and ferrous sulfate be taken at the same time of the day?

A. No. Iron supplements such as ferrous sulfate interfere with the absorption of Synthroid (levothyroxine) taken to treat thyroid problems. Wait at least two hours after Synthroid before taking iron, calcium or other minerals.

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  1. Katie R
    Reply

    So, if you are supposed to wait a couple hours after taking synthroid to take calcium or iron, what about my the calcium and iron in my breakfast foods? Is the amount not enough to interfere or should I change what I eat?
    Thanks.

  2. D
    Reply

    Calcium can not be taken with Iron- it binds to it. Many medications bind with iron and calcium respectively. High blood pressure meds … Etc. Sooo… Take Synthroid early am. Take Iron with breakfast and Vitamin C, no dairy in meal. My low iron dosage 325 mgs. Take Calcium with Dairy – small amount an hour after dinner. Stay away from dairy until Iron levels are up- and always keep it away from thyroid meds.
    And for those of you who like to let your Dr. manage the levels- unless he is doing all of the levels every time- that is why you feel bad. Take charge and responsibility for your health.
    Thyroidectomy and a biologist

  3. Cher
    Reply

    I have taken synthroid for over 30 years. It was only about 10 years ago that a friend informed me that I shouldn’t eat grapefruit at all. My doctor prescribed less medication as a result. It has only been in the last few weeks that the pharmacist has labeled my synthroid with a “do not take with iron and calcium.” I have been drinking coffee with milk, eating breakfast with milk followed by a multivitamin all these years. I rely on my doctor and lab tests to keep my thyroid levels and dosage in sync.

  4. janet
    Reply

    I couldn’t tolerate iron pills either. But I now take liquid iron (floradix) twice a day and it seems to help…plus it is much easier on the digestive system.
    Peoples Pharmacy response. Take your iron, even liquid iron, at least two hours after the Synthroid.

  5. cw
    Reply

    I live in the country so we have well water. Our water is very high in iron. Even with the water softener I fight rust stains. Will this iron interfere with my synthroid?

  6. Mo
    Reply

    Hi,
    I thought about doing this, too. Since you are taking the iron and calcium at night, do you think you still have the energy you would have if you took them earlier in the day?

  7. BH
    Reply

    Some pharmacists are brilliant. And some doctors are brilliant. Likewise in either case, the converse can be true. However to claim one profession knows it’s business better than the other knows its stuff, is to wield a pretty broad brush. Also there is a significant difference between the pharmacy profession and the medical one (and I speak as an educated consumer here, and not a member of, nor in any way affiliated with, either profession): The latter involves the training to not only competently recite book knowledge, but also to assume the personal hands-on responsibility of arriving at safe and effective clinical decisions, anew with each individual patient, multiplied many times over in a day. In contrast the former’s role, in the above regard, is that of a formal information support resource.

  8. DS
    Reply

    Pharmaceutics know more about drugs than doctors from my experience plus doctors have only one class in medical school on nutrition. No one told me for years when to take synthroid or supplements. I think alternative doctors do know more bout this. Be sure and ask if your doctor is up to date on the Endocrinology Academy scale to determine hypothyroidism. It has changed and many doctors have not kept up with that therefore, many people are not properly diagnosed and have many thyroid issues but told they are in the range which is incorrect in many cases if they are not up to date!!! It is also best not to take a generic as the batches are not consistent.

  9. BH
    Reply

    The advice not to take my thyroid pill (Synthroid) together with my iron supplement is exactly what my pharmacist told me. Yet my doctor doesn’t seem to think it matters a whole lot. So I considered why my doctor would seem to contradict the pharmacist, and a logical explanation easily occurred to me: It’s because my doctor routinely sends me to the lab to have my plasma thyroid hormone levels checked.
    Since the doctor’s choice of Synthroid dosage to have me on is solely determined by what my plasma thyroid hormone levels are, if these levels remain okay, it truly does not matter. And if my iron supplement were for some reason to abruptly begin to interfere with my thyroid, the change in my plasma thyroid hormone level lab values would signal the doctor to adjust my Synthroid dosage accordingly, and that would be all there is to it.
    Yes, it’s good for us health consumers/patients to be aware of certain facts, which doctors often don’t view us as needing to be made aware of. But I can understand where the doctors are coming from, since some (yet by no means all, mind you) of us will often misconstrue a fact due to a less than whole comprehension of the fact’s context.

  10. linda
    Reply

    I have been taking synthroid for 2 yrs. due to a thyroidectomy but now I also found out I am low in iron, vitamin d and calcium… I take synthroid in morning and I was reading I should take iron at night, but can you take calcium and iron at same time? Thanks for any input!
    PEOPLE’S PHARMACY RESPONSE: IT IS MORE IMPORTANT NOT TO TAKE EITHER CALCIUM OR IRON WITH SYNTHROID THAN IT IS NOT TO TAKE THEM WITH EACH OTHER. THEY DO INTERFERE WITH EACH OTHER’S ABSORPTION SOMEWHAT, BUT THEY BOTH REALLY INTERFERE WITH SYNTHROID.

  11. Mary Ellen
    Reply

    I am anemic and just started taking Iron again per doctor’s request. I have been taking my Synthroid and iron together. Last night I was so tired that I went to bed at 7:30 p.m. Today I started thinking that maybe the iron was negating the Synthroid – so didn’t take it this morning. After reading everyone’s comments on this website and other websites, I now know for sure to take my iron at night.

  12. Natalie
    Reply

    I was informed and have done research on this matter, that Snythroid should be taken on a completely empty stomach, and also no food should be consumed approximately 2 hours after you take the pill. I also have anemia, and need to take an iron supplement. I solve this dilemma the following way: First thing in the morning (like with in 5 minutes) I take my synthroid with *water. Then, I get ready etc. I grab breakfast on the way to work and eat once I get there. This usually eats up the 2 hour time slot I need to let the snythroid start to do it’s job.
    *remember not to take your synthroid with OJ or milk etc. as it makes the medicine ineffective.
    In the evening before bed, I take my iron supplement and my daily vitamin.
    I hope this helps everyone. It’s really frustrating when you need two pills that you can’t take at the same time of the day, and both are responsible for giving you energy to make it through the day!!!

  13. Pam
    Reply

    Because synthroid is absorbed in the lower intestine, I heard you should wait at least four hours before taking synthroid and calcium and/or iron supplements.
    PEOPLE’S PHARMACY RESPONSE: IT WOULD BE BEST TO TAKE THE SYNTHROID FIRST THING IN THE MORNING (OR LAST THING AT NIGHT) ON AN EMPTY STOMACH, THEN WAIT TO TAKE CALCIUM OR IRON SUPPLEMENTS.

  14. Anita F.
    Reply

    Hi,
    I did not know that I should not take Synthroid with Calcium & Iron.
    I have been taking them with breakfast every day for 4 months now, and as a result, I am convinced that this is why I have been having all these symptoms of feeling dizzy, very cold all the time, numbness in fingers and toes, sore, achy hands and feet.
    Now I know. Do not take Synthroid with Food, wait at least 1\2 hour, then have your meal, and wait 2 hours before taking other supplements.
    Thanks.

  15. RichardS
    Reply

    Same effect w/other irons such as ferrous fumarate? (in my Trader Joe’s Multiple Vitamin & Minerals)

  16. FLM
    Reply

    My doctor first noticed I had a low white blood count and after several test sent me to a blood specialist. He did after several visits a bone marrow and found I had no iron in my storage system. He gave me a infusion of iron, but this has not brought my count up. I cannot tolerate iron vitamins. I have tried eating food containing iron, but this has not helped. I have started taking a One A Day Vitamin For Women. Any help for this would be very appreciated.

  17. Marge
    Reply

    I have taken my synthroid for years with iron. I have this listed with all my meds & supplements with the time taken. I give this list whenever I go to the Doctor. Not one has ever informed me that this is bad.
    This an example of why we need to check every aspect of our care & not just rely on the medical profession to keep us informed.
    Thanks for helping to keep us informed.

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