Vitamin B3, which is usually medically referred to as niacin, comes in 3 forms: nicotinic acid, Niacinamide and Inositol Hexaniacinate. It is good for preventing low levels of riboflavin (riboflavin deficiency), cervical cancer, and migraine headaches. It is also used for treating riboflavin deficiency, acne, muscle cramps, burning feet syndrome, carpal tunnel syndrome, and blood disorders such as congenital methemoglobinemia and red blood cell aplasia. Some people use riboflavin for eye conditions including eye fatigue, cataracts, and glaucoma. Other uses include increasing energy levels; boosting immune system function; maintaining healthy hair, skin, mucous membranes, and nails; slowing aging; boosting athletic performance; promoting healthy reproductive function; canker sores; memory loss, including Alzheimer's disease; ulcers; burns; alcoholism; liver disease; sickle cell anemia; and treating lactic acidosis. The niacin RDA for males aged 14 and over is 16 milligrams per day, and females aged 14 and over need 14 milligrams of niacin per day. Symptoms of mild B3 deficiency include indigestion, fatigue, canker sores, vomiting, poor circulation and depression. Severe deficiency can cause a condition known as pellagra. Pellagra is characterized by cracked, scaly skin, dementia, and diarrhea. However, at high doses niacin can also be toxic. The Most Common Niacin Side Effects are : Nausea or vomiting, skin reactions, rashes, headaches, dizziness, allergic reactions, heart problems, diabetes, worsened gallbladder or liver disease symptoms, aggravated gout symptoms, low blood pressure, or stomach or intestinal ulcers.