The diuretics are generally divided into four major classes, which are distinguished by the site at which they impair sodium reabsorption [1,2]: âLoop diuretics act in the thick ascending limb of the loop of Henle.
Night blindness, also known as nyctalopia, is the inability to see clearly at night or in dim light (such as raining or dark room). Nyctalopia is not an eye disease or disorder. It is actually a symptom or indication of an underlying problem in which some may be serious.
Causes of Night Blindness. Night blindness, sometimes referred to as nyctalopia or impaired dark adaptation, is due to a disorder of the cells in the retina that are responsible for vision in dim light. It can be a symptom of a number of conditions that can be acquired or congenital (present at birth): Vitamin A deficiency: Night blindness is one of the first signs of vitamin A deficiency, which is commonly associated with malnutrition. 2  The vitamin deficiency often develops in malnourished children who are too young to recognize a problem with their night vision or report a vision problem.