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Mental health includes our emotional, psychological, and social well-being. It affects how we think, feel, and act as we cope with life. It also helps determine ...
What are opioids? Opioids, sometimes called narcotics, are a type of drug. They include strong prescription pain relievers such as oxycodone, hydrocodone, ...
What are opioids? Opioids, sometimes called narcotics, are a type of drug. They include strong prescription pain relievers, such as oxycodone, hydrocodone, ...
What are opioids? Opioids, sometimes called narcotics, are a type of drug. They include strong prescription pain relievers such as oxycodone, hydrocodone, ...
The optic nerve is a bundle of more than 1 million nerve fibers that carry visual messages. You have one connecting the back of each eye (your retina) to ...
What is oral cancer? Oral cancer is cancer of the mouth. It is a type of head and neck cancer. Most oral cancers are squamous cell cancers. They begin ...
Organ donation takes healthy organs and tissues from one person for transplantation into another. Experts say that the organs from one donor can save or help ...
You may need an organ transplant if one of your organs has failed. This can happen because of illness or injury. When you have an organ transplant, doctors ...
Some people have naturally straight teeth that fit together. But if you have problems with your bite or the spacing of your teeth, you may need orthodontic ...
What is osteoarthritis? Osteoarthritis, sometimes called OA, is a type of arthritis that only affects the joints, usually in the hands, knees, hips, neck, ...
Osteogenesis imperfecta (OI) is a genetic disorder in which bones fracture (break) easily. Sometimes the fractures happen for no known reason. OI can also cause weak ...
Osteonecrosis is a disease caused by reduced blood flow to bones in the joints. In people with healthy bones, new bone is always replacing old bone. In osteonecrosis, ...
What is osteoporosis? Osteoporosis is a disease in which your bones become weak and are likely to fracture (break). The disease can develop when your bone ...
An ostomy is surgery to create an opening (stoma) from an area inside the body to the outside. It treats certain diseases of the digestive or urinary systems. ...
What is ovarian cancer? Cancer is a disease in which abnormal cells in the body grow out of control and form a tumor. Ovarian cancer is a cancerous tumor ...
The ovaries are part of the female reproductive system. They produce a woman's eggs and make female hormones. Ovarian cysts are fluid-filled sacs in or on ...
What are ovaries? The ovaries are a pair of female reproductive glands that make eggs and female hormones. Women have one ovary on each side of the uterus ( ...
Over-the-counter (OTC) medicines are drugs you can buy without a prescription. Some OTC medicines relieve aches, pains, and itches. Some prevent or cure diseases, ...
Overactive bladder is a condition in which the bladder squeezes urine out at the wrong time. You may have overactive bladder if you have two or more of these symptoms: ...
What is oxygen? Oxygen is a gas that your body needs to work properly. Your cells need oxygen to make energy. Your lungs absorb oxygen from the air you ...
