In my practice, I see many thyroid patients who are taking their medication regularly, yet their TSH levels remain out of range. One of the most common — and overlooked — reasons is how and when they take their medicine relative to food.
Levothyroxine (thyroxine / T4 replacement medicine) is one of the most absorption-sensitive medications in existence. Certain foods, drinks and minerals can dramatically reduce how much gets into your bloodstream — and this directly affects your thyroid control.
This is the single most common mistake I see in my Kolkata patients: they wake up, take their thyroid tablet, and immediately have a cup of chai with milk. This almost completely nullifies the medication absorption — the calcium in milk and the tannins in tea both interfere with thyroxine uptake.
If you've been doing this for months, it explains why your TSH hasn't normalised despite regular medication. The fix is simple: wait at least 45–60 minutes after your tablet before having chai or any dairy.
Many thyroid patients also take other medications. These should not be taken simultaneously with thyroxine:
The general rule: thyroxine should be taken alone, on an empty stomach, with plain water only.
When a patient's TSH is not responding to medication, I always ask three questions: Are you taking it on an empty stomach? How long are you waiting before eating? Are you taking it with water or something else? In most cases, correcting one of these answers resolves the problem without changing the dose.
If your TSH is still off despite regular medication, book a review — it could be something as simple as timing or a dose adjustment.