Abstract
Long QT is a disorder of the heart's conduction system. It can be congenital or acquired. The acquired type is caused mainly by medications. The diagnosis of LQT depends on the clinical features, the family history, and the ECG findings. The clinical presentations range from dizziness to syncope and sudden death. The dentist should consult the cardiologist to avoid any complications that may put the LQTS patient at risk. Medications such as erythromycin and antifungals are contra-indicated and should not be prescribed. Local anaesthetics containing adrenaline and bupivacaine should be avoided. Stress can precipitate symptoms and lead to sudden death.