Question: What causes Long QT syndrome ?
Answer: What causes long QT syndrome? Acquired long QT syndrome can be caused by certain medicines and medical conditions. Some medications that cause long QT syndrome include antihistamines and decongestants, antibiotics, antidepressants, and cholesterol-lowering medicines. Examples of medical conditions that can cause long QT syndrome include excessive diarrhea or vomiting and certain thyroid disorders. Inherited forms of long QT syndrome are caused by changes in genes that control the heart muscles electrical activity. Inherited long QT syndrome may be isolated (occur alone without other associated symptoms) or be due to a genetic syndrome, such as Romano-Ward syndrome, Jervell Lang-Nielsen syndrome, Anderson-Tawil syndrome, and Timothy syndrome.
Source: GARD