Use of quinine is characterised by a frequently experienced syndrome called cinchonism. It is possible this action is the root cause of cinchonism. Arrhythmias, cinchonism, and hemolytic uremic syndrome can also occur at higher dosages. Quinidine toxicity can lead to cinchonism and also to quinine amaurosis. Cinchonism can occur from therapeutic doses of quinine, either from one or several large doses.