Mainstream endocrinologists seem to be moving grudgingly toward acceptance of combination T4 plus T3 therapy for hypothyroidism. A great example of the mixed feelings harbored by endocrinologists in this regard is the title of a recent editorial, “ Combo (treatment) a Last Resort for Hypothyroidism” . Although the author, Dr. Bruce Jancin of the University of Colorado, recognized the value of combination T4 plus T3 therapy, he did so with the least possible enthusiasm. In his article the doctor acknowledged the weakness of scientific studies showing negative results with combination therapy and pointed out the findings of the Watts Study which provides a genetic rationale for why some people need to have T3 added to T4 to return to proper thyroid hormone balance.
Since there is no financial incentive for promoting combination T4 and T3 therapy (or Armour Thyroid which provides similar benefits), I expect combination therapy will remain relatively unknown and under utilized by the medical community in the U.S. One factor that could alter this scenario is the patenting of a slow release form of T3. If this potentially lucrative product ever reaches the market a sales force would certainly be hired to get doctors to begin using this approach.