Thyroid is the most critical hormone in the body. Its functions are numerous. Sadly, it has not been prescribed properly to patients, for years. It is usually prescribed only in the Thyroxine or T4 form, only. However, the active form is Tri-iodothyronine or T3. The justification was that T3 has a very short half-life and the body can convert T4 into T3. This sounds good in theory but mature patients (over 40) or hypothyroid patients do not seem to have this ability and cannot convert the T4 into T3, as the enzyme responsible for this, 5’-de-iodinase, does not appear to be adequately functional or present. Hence, their blood levels (measured by TSH) seem to improve but clinically the patient remains unaffected. Free T3 levels, also, do not improve.

This problem is overcome when a combination of T3 and T4 are compounded.  However, younger patients do not seem to require as much T3, so their combination differs from the over-40 preparation. Yuvanesse Pharmacy produces many combinations of T3:T4, based on the doctor’s prescription. We use only natural T3 and T4. We do not use pig thyroid extracts.