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A member asked:

Could too much synthroid (thyroxine) cause heart block?

A doctor has provided 1 answer

Thyroid: Too much synth rood would usually cause too rapid a heart rate. In an occasional patient the tachycardia could have some av block associated. Too little thyroid would be a more common cause of block.

Answered 10/20/2013

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Related Questions

A member asked:

Could missing at least 5 days of Synthroid cause heart racing and late periods? I have been on Synthroid for 3 yrs and this is the most I have missed.

A doctor has provided 1 answer

A member asked:

Taking Synthroid (thyroxine) 125 and felt a sudden adrenaline rush on my heart. Should i be worried?

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A member asked:

I've been off my Synthroid (thyroxine) 50 mcg for three weeks now will i go into a coma or something? Will it damage my heart? I am starting meds again soon

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A member asked:

I've been having palpitations and a fluttery heart. My GP says i am on too much thyroxine. Is it dangerous for my heart? How does she know it's that?

4 doctors weighed in across 2 answers

A member asked:

Can someone be sensitive to different dosages of synthroid (thyroxine)? From 75 to 88. In my right range @ 88 and feel great, but feel pounding heart and anxiety

A doctor has provided 1 answer

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