The heart is the organ that pumps blood, with its life-giving oxygen and nutrients, to all tissues of the body. If the pumping action of the heart becomes inefficient, vital organs like the brain and kidneys suffer.And if the heart stops working altogethe...

A headache is pain or discomfort in the head, scalp, or neck. Serious causes of headaches are extremely rare. Most people with headaches can feel much better by making lifestyle changes, learning ways to relax, and occasionally by taking medications. H...

Head lice (Pediculus capitis) are small parasitic insects exquisitely adapted to living mainly on the scalp and neck hairs of their human host. Their six impressive legs are elegantly evolved to grasp hair shafts and provide a striking example of biologic...

Hair loss is a big worry to many people, both male and female. If you have a worrying amount of hair in the basin after shampooing, you may think you are on the way to baldness. But this is not usually the case. The 50–100 hairs that everyone loses each...

Gestational diabetes is a kind of diabetes that can happen during pregnancy. Out of every 100 pregnant women, 3 to 5 develop gestational diabetes. Like other kinds of diabetes, gestational diabetes is a condition in which your body has trouble managing th...

Genital warts, also known as venereal warts, or condylomata acuminata, are caused by the human papilloma virus (HPV). More than 100 types of HPV are known to exist. Low risk types (HPV 1, 2, and 3) cause warts on the hands, feet, and other parts of the bo...

Genital herpes is a sexually transmitted disease, or STD. (This means it spreads from person to person during vaginal, anal, or oral sexual contact.) It is caused by a virus. Genital herpes is one of the most common STDs in the United States. Who gets ...

Gastroenteritis is simply a medical term for inflammation of the stomach and intestines, usually due to food poisoning or a viral illness. It is very common and the usual symptoms include loss of appetite, nausea, vomiting, tummy pain and diarrhoea. Th...

Gastritis, a condition that involves the irritation and inflammation of the stomach, afflicts millions of people. Any number of things causes it, from injury to bacteria. In that respect, it is akin to a headache: It can strike anyone, and it can be cause...

Gallstones are hard, pebble-like deposits that form inside the gallbladder. Gallstones may be as small as a grain of sand or as large as a golf ball, depending on how long they have been forming. Causes, incidence, and risk factors Most people who ...

Food poisoning comes from eating foods that contain germs like bad bacteria or toxins, which are poisonous substances. Bacteria are all around us, so mild cases of food poisoning are common. You may have had mild food poisoning — with diarrhea and an up...

Influenza, commonly shortened to "flu," is an extremely contagious respiratory illness caused by influenza A or B viruses. Flu appears most frequently in winter and early spring. The flu virus attacks the body by spreading through the upper and/or lower r...

Fibromyalgia is an arthritis-related condition characterized widespread muscle pain and the presence of tender points, or areas of the body that are particularly sensitive to pressure. Other symptoms may include sleep disturbances, severe fatigue, depress...

Fibroids are tumours that grow in the uterus (womb). They are benign, which means they are not cancerous, and are made up of muscle fibre. Fibroids can be as small as a pea and can grow as large as a melon. It is estimated that 20-50% of women have, or wi...

Hemorrhoids are swollen anal varicose veins. These veins can become so stretch that they push with extreme force, then rupture and bleed. The hemorrhoids cause rectal bleeding, pain, burning, inflammation, irritation and itching, since the swollen tissues...