Browse comprehensive, doctor-reviewed information on 50 health conditions.
Lyme disease is an infectious disease caused by the bacterium Borrelia burgdorferi, transmitted through the bite of infe...
Major depressive disorder (MDD), commonly known as depression, is a mood disorder that causes persistent feelings of sad...
A migraine is a type of headache that can cause severe throbbing pain or a pulsing sensation, usually on one side of the...
Multiple sclerosis (MS) is a disease in which the immune system eats away at the protective covering of nerves. It can c...
Obesity is a complex disease involving an excessive amount of body fat. It is not just a cosmetic concern — it increas...
Osteoporosis is a condition that weakens bones, making them fragile and more likely to break. It develops slowly over se...
Ovarian cancer is a type of cancer that begins in the ovaries. It often goes undetected until it has spread within the p...
Pancreatic cancer begins in the tissues of the pancreas. It has a poor prognosis because it seldom causes symptoms early...
Parkinson's disease is a progressive nervous system disorder that affects movement. Symptoms start gradually, sometimes ...
Polycystic ovary syndrome (PCOS) is a hormonal disorder common among women of reproductive age. Women with PCOS may have...
Pneumonia is an infection that inflames the air sacs in one or both lungs. The air sacs may fill with fluid or pus, caus...
Prostate cancer is cancer that occurs in the prostate gland. It is one of the most common types of cancer in men. Most p...
Psoriasis is a chronic autoimmune skin disease that speeds up the life cycle of skin cells, causing cells to build up ra...
Rheumatoid arthritis (RA) is a chronic autoimmune disease that primarily affects the joints. It causes the immune system...
Shingles (herpes zoster) is a viral infection that causes a painful rash. It is caused by the varicella-zoster virus, th...
Skin cancer is the abnormal growth of skin cells, most often developing on skin exposed to the sun. The three major type...
Sleep apnea is a serious sleep disorder in which breathing repeatedly stops and starts during sleep. Obstructive sleep a...
A stroke occurs when the blood supply to part of the brain is interrupted or reduced, preventing brain tissue from getti...
Type 2 diabetes is a chronic condition that affects the way the body processes blood sugar (glucose). With type 2 diabet...
A urinary tract infection (UTI) is an infection in any part of the urinary system — kidneys, ureters, bladder, or uret...