T4/3 combo

[Karen-Eleanor]

I’ve been taking Armour Thyroid for over 20 years. Previously on NHS but we moved house to a different area and new GP wouldn’t even discuss it. Armour Thyroid is now very expensive and not easy to obtain. I’m concerned about the long term importing and prescribing issues. Long scenario but now under Endo at local hospital who has agreed to prescribe T4/T3 combo. Has anyone else made this change? Are there any pitfalls ? I’m concerned as I’ve done well (most of the time) on NDT.

[helvella Administrator Thyroid UK]

From what members have posted, one pitfall to avoid is deciding on doses of T4 + T3 which arithmetically mimic the apparent potency of the Armour Thyroid.

That might not seem unreasonable but rate of absorption, etc., are different so exact numbers simply don't appear to work.

Unfortunately, the worst impact will likely be at the start of changing over. Obviously, when you have been on a combination for a while, you are able to judge where you are - backed up by blood test results.

I don't know the best approach - but having sufficient T4 and T3 and the ability to adjust if it feels terrible from day one seems a good start point. No idea how you explain that to a consultant.

I'm hoping those with experience can jump in and tell you what they did.

[SlowDragon Administrator]

Things to consider

Brand of levothyroxine

Brand of T3

Test 6-8 weeks after any dose or brand change

Test Vitamin levels