Thyroid UK
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Optimum time for re-testing bloods

I want to go for a re-test of my bloods as some symptoms seemed to have increased. It could be due to my not taking the tablet correctly so I need to maximise the opportunity for a true reading. Could I clarify? What is the minimum time you stay off eating in the morning in order to take your Levo so it can work effectively? Can you drink tea/coffee during this time ?And how long does it take to establish itself in the body once you start taking it correctly?

I think that I may have got into some bad habits over some weeks now , I have not left it long enough before eating, thus rendering my medication ineffective. So I need to rule that scenario out before I request a re-test of my bloods plus leave it long enough for the medication to really take hold.

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Levothyroxine should be taken with a glass of water on an empty stomach, one hour before, or two hours after, food and drink. Two hours away from supplements and other medication and 4 hours away from vitamin D, calcium, iron and oestrogen.

You will have been absorbing some of the Levothyroxine so it won't have been ineffective but perhaps not as effective as it could have been. 4 weeks should be long enough to improve absorption for retesting..

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Thanks Clutter for the clarification


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