The Medicines and Healthcare products Regulatory Agency (MHRA) has issued a reminder about the QT-interval-prolonging effect of quinine.1 The MHRA has also provided advice on prescribing quinine alongside other medicines that prolong the QT interval. Quinine has dose-dependent QT-interval-prolonging effects and should be used with caution in patients with risk factors for QT prolongation or in those with atrioventricular block.

Prolongation of …