Mandy, Unfortunately they don't specify how much T4 and T3 the tablets contain. As you've been taking NDT you may not need to start as low as half a tablet.
Website says: Typically most people need to build up over several weeks to a level between 1½ and 2½ tablets daily.
Begin by taking half to one tablet daily*. Generally it is found to be safe to start at a half tablet daily (providing the heart is not weak) and to hold at that dose for 3 to 14 days (an absolute minimum of 3 days).
*Some very sensitive individuals may even find half a tablet daily overly stimulating in which case start at ¼ tablet daily.
Increase the amount you are taking by half tablet and maintain that amount for another three to fourteen days before increasing again; until you feel you have achieved your optimal level.
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