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Malaise and fatigue are common symptoms of a wide-ranging list of ailments. Malaise refers to an overall feeling of discomfort and lack of well-being. Fatigue is extreme tiredness and lack of energy or motivation for everyday activities.
Marcus Gunn syndrome is a congenital condition where a drooping eyelid briefly opens wider and appears to wink when the jaw is moved.
The meatus is the opening in the penis where urine (pee) comes out. In meatal stenosis, the meatus is too small.
Learn more about MCL injuries and how they're treated.
A meibomian cyst, or chalazion, is a lump on the inner side of the eyelid. It occurs when one of the small oil glands becomes blocked.
Learn about this rare but serious condition in which bacteria invade the membranes around the brain and spinal cord.
Sometimes viruses can spread to the meninges, the membrane around the brain and spinal cord, and cause more severe illness. Learn about it here.
Learn about types of mental disorders and conditions that affect thinking and behavior.
Metabolic syndrome is a group of separate health problems that often happen together in a person.
Microcephaly is a rare condition in which a child's brain doesn't fully develop, resulting in an abnormally small head size.
