Another Thumbs Down for T4/T3 Combination Therapy

In a recent interview with OB.GYN News, Dr. Hossein Gharib, past president of the American Association of Clinical Endocrinologists, and professor at the Mayo Clinic, weighed in with his opinion regarding use of T3 in combination with T4 to treat hypothyroidism (low thyroid function). The doctor’s opinion was that there is no scientific support for the use of combination T4/T3 treatment. He points to several good studies in the last 5 years that fail to show a measurable benefit of using treatment combining the two hormones versus standard T4 treatment alone.

I suppose that wraps it up. At least as far as the professor is concerned.

But statements scattered through the interview provide hints of the expert’s lingering doubt about what is really going on here. For instance, he notes that although most patients do well on T4 therapy alone some still complain of fatigue, low energy, weight gain, or depressed mood despite adequate levels of T4 replacement. Despite acknowledging this widely observed problem the reason for continued complaints remains unexplained. Later he goes on to say that if the patient insists on trying T3/T4 combination therapy despite adequate T4 replacement therapy, he documents the conversation and adds T3 to the therapy. Does his eventual willingness to add T3 suggest an underlying uncertainty about his “scientific” conclusions.

Why would a patient “insist” on combination therapy in the face of such esteemed advice? According to the interview Dr. Gharib believes this misplaced hope is due to the use of the Internet where patients have read that when treating hypothyroidism, mood improvements can be seen after adding T3 to therapy. We are left to assume health information acquired over the Internet is used only by the gullible or neurotic.

What is missing from the interview is the doctor’s experience when he finally breaks down and adds T3 to T4 treatment. I bet the doctor is frequently surprised by the positive outcome of this intervention. If the patient reports improvement is it due to the neurotic expectations of the patient rather then a physical response? All those “good” studies couldn’t be wrong, after all.

I have analyzed many of the studies which focus on combination T4/T3 treatment. It is my opinion these studies aren’t nearly as good as generally believed. At my reviews of these studies are at the following links: , , ,

I believe the flaw in this controversy lies more with the methods of the medical researchers rather than misguided Internet reading patients. The doctor in this interview is a highly regarded and accomplished endocrinologist but not necessarily unaffected by his peers. I have little doubt at this time our “thought leaders” regard T4/T3 combination treatment of hypothyroidism as the providence of the Internet and the gullible. Endocrinologists who disagree with the influential majority by endorsing T4/T3 therapy for treatment resistant patients face the same fate as the caveman in Geico commercials. No respect.

The statements made by Dr. Pepper and associates at are for educational purposes only and should not be viewed as medical advice. Only you and your personal physician can decide on the best treatment for you.

Gary Pepper, M.D., FACP

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