<prompt> False about quinidine in isIt increases effective refractory periodUsed in hypeensionCauses paradoxical tachycardiaCinchonism is seen  <response>: Refer kDT 6e p 511,512 Quinidine has following propeies; Class 1a and 3 antiarrhythmic propeies Increase the effective refractory period Anti vagal action causes tachycardia. This tachycardia is paradoxical, because quinidine is a cardiac depressant and does not expected to increase the hea rate some Alpha blocking propey is and its use can cause hypotension and is not used for antihypeensive agent. At higher doses, Cinchonism occurs, characterized by ringing in ear, veigo, headache and visual disturbances ,mental changes and delirium Antimalarial action is Poorer than quinine. ECG changes:increase PR and QT interval, and broadens QRS complex, and change the shape of T wave 