Mercaptizol induced Hypoglycemia: A Case Report

A 22-year-old female Ashkenazy Jewish previously healthy complaint on weakness

In glucometer, her sugar level was 50 mg% and she felt better after ingestion of a small amount of sugar.

3 weeks ago while traveling in Peru, she developed thyrotoxicosis and was started mercaptizol 30 mg a day and deralin.

She didn’t drink iodine (iodinated preparations for water purification) while traveling and had no pain or fever. In physical examination there where no goiter or exophthalmos
While I saw her she was already euthyroid and felt quite good except for tiredness.
In literature, we found few case reports of mercaptizol and PTU-induced insulin autoantibodies which cause symptomatic hypoglycaemia.
Most cases were described in the Asian population and resolved a few weeks after stopping the drug.
In our patient, the hypoglycaemia resolved after only one episode.
We don’t have the insulin level nor antibodies titer yet.
My conclusion is that physicians should be aware of Mercaptizol and PTU induced hypoglycemia which can be life-threatening