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Obesity

Obesity means having too much body fat. It is different from being overweight, which means weighing too much. The weight may come from muscle, bone,……

Obesity in Children

Obesity means having too much body fat. It is different from being overweight, which means weighing too much. Both terms mean that a person’s weight……

Ocular migraine

Ocular Migraine

Ocular migraine, also known as a visual migraine or a migraine with aura, is a type of migraine headache that is characterized by temporary visual……

Opioid

What Are Opioids? Opioids are a class of drugs that include the illegal drug heroin, synthetic opioids such as fentanyl, and pain relievers available legally……

Opioid Addiction

A substance used to treat pain or cause sleep. Opiates are made from opium or have opium in them. Opiates bind to opioid receptors in……

Osteoarthritis

Osteoarthritis

Osteoarthritis is the most common form of arthritis. It causes pain, swelling, and reduced motion in your joints. It can occur in any joint, but……

Osteogenesis Imperfecta

Osteogenesis imperfecta (OI) is a genetic disorder in which bones break easily. Sometimes the bones break for no known reason. OI can also cause weak……

Osteonecrosis

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……

Over-the-counter drug

Over-the-counter (OTC) drugs are medicines sold directly to a consumer without a prescription, from a healthcare professional, as compared to prescription drugs, which may be……

Over-the-Counter Medicines

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, like……