Doctors and patients have been at each other’s throats for decades over how to treat a little gland in the neck—and patients may be gaining ground.

The butterfly-shaped thyroid gland produces hormones that regulate virtually every system in the body. Not enough production of thyroid hormones, known has hypothyroidism, can cause fatigue, weight gain, depression and other metabolic and fertility problems. Too much, the less common hyperthyroidism, can cause heart palpitations, tremors and bone loss.

Because those symptoms can have several other causes, many doctors diagnose thyroid disorders mainly with blood tests. Many also rely on a single form of treatment for hypothyroidism, which has made the synthetic hormone levothyroxine (Synthroid and other brands) among the most prescribed medications in the world.

But a vocal group of patients say they haven’t gotten better on levothyroxine, though their blood tests have returned to normal. They’ve banded together online to share their frustrations and promote alternative therapies.

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Some top endocrinologists are coming around to their view. Studies have confirmed that 5 percent to 15 percent of patients don’t get better on levothyroxine alone. Discoveries of gene variations may help explain why.

“More doctors are thinking, ‘Have we missed something? Could there be a role for combination therapy in some patients?’ ” says Jacqueline Jonklaas, an endocrinologist at Georgetown University Medical Center.

“I credit this to patients pushing doctors and saying, ‘You don’t know what you’re talking about. I don’t feel fine,’ ” says Antonio Bianco, president of the American Thyroid Association. Dr. Bianco, who is also chief of endocrinology at Rush University Medical Center in Chicago, says he has refocused the research to search for answers for such patients.

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