Examine patient for a potent tachycardia & a temporary decrease in BP during infusion. History of brain damage (eg, stroke or severe brain injury); tendon inflammation/complaints; pseudomembranous colitis; family history of or current G6PD deficiency; mental health problems; symptoms due to nerve damage eg, kinetic or sensory problems in hand & feet. Prolonged QT interval, salt imbalance in the blood, bradycardia, heart failure, MI. Skin may become more sensitive to light while on medication. Renal & hepatic impairment. Concomitant use w/ anticoagulants eg, warfarin; oral medicine that lowers blood glucose levels; medicines that result in abnormal ECG changes. Patients on a controlled Na diet & fluid restriction. May impair ability to drive & use machines. Pregnancy & lactation.