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39 Search results starting with "O"

Disease

Occupational asthma

Dust, fumes and other substances at work can cause asthma. Find out how to recognize this common type of asthma.
Disease

Ocular rosacea

Learn about symptoms, causes and treatments of ocular rosacea — an eye condition that often affects people who have skin rosacea.
Disease

Oligodendroglioma

Learn about this type of tumor that can occur in the brain or spinal cord.
Disease

Oppositional defiant disorder (ODD)

This childhood mental health condition includes frequent and persistent anger, irritability, arguing, defiance or vindictiveness toward authority.
Disease

Optic neuritis

Learn about this painful eye disorder that affects your optic nerve and what your doctor may recommend for treatment.
Disease

Oral lichen planus

This ongoing inflammatory condition results in white, lacy patches or red, swollen tissues or open sores inside your mouth that may cause burning or pain.
Disease

Oral thrush

This infection is caused by the overgrowth of the fungus Candida albicans in the mouth.
Disease

Orchitis

This infection of one or both testicles can cause pain and infertility. A bacterial infection or the mumps virus is the usual cause.
Disease

Orthostatic hypotension (postural hypotension)

This form of low blood pressure might cause dizziness, lightheadedness or fainting when rising from sitting or lying down.
Disease

Osteoarthritis

This most common form of arthritis mainly affects joints in your hands, knees, hips and spine. There's no cure, but symptoms can be managed.
Disease

Osteochondritis dissecans

Osteochondritis dissecans most commonly affects children who are very active in sports. Learn about the symptoms and treatment of this joint condition.
Disease

Osteomyelitis

Bones don't get infected easily, but a serious injury, bloodstream infection or surgery may lead to a bone infection.
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