People with Graves disease often have brain-related symptoms like brain fog and mood swings, but doctors sometimes think these are just stress or hormonal issues, so it takes longer to diagnose the real cause.

A young adult had sudden psychosis — like hearing voices and mood changes — and it turned out to be the first sign of an overactive thyroid caused by an immune system problem. This shows that sometimes, mental health symptoms can actually be caused by a physical illness.

Sometimes, a serious thyroid problem called Graves’ disease in young adults can come with mental health symptoms like hearing voices, mood swings, trouble sleeping, and memory issues — and both the thyroid and mental symptoms might get better with the right medicines.