Retinopathy, hepatic or renal disease or concomitant use w/ drugs affecting these organs. Quinine sensitivity; GI, neurological, blood disorders; G6PD deficiency, porphyria, cutanea tarda, psoriasis. Galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption. Carry out ophthalmological exam before initiating treatment & repeat at least every 12 mth. Long-term therapy (perform periodic exam of skeletal muscle function & tendon reflexes), severe hypoglycemia, cardiomyopathy resulting in cardiac failure. May impair ability to drive or operate machinery. Childn sensitivity. Lactation.