In this heart condition present at birth, two major blood vessels aren't attached to the heart in the usual positions. Learn how it's treated.
Disease
Down syndrome
In this genetic condition, an unusual cell division results in extra genetic material from chromosome 21. This causes delays in growth and development.
Disease
Dressler syndrome
Learn about the symptoms and treatment of this condition that involves swelling and irritation of the sac around the heart after damage to the heart muscle.
Disease
Drug addiction (substance use disorder)
Drug addiction affects your brain and behavior to the point where you can't control your use of legal or illegal drugs, even when you know they cause harm.
Disease
Drug allergy
Learn which medicines are more likely to cause an allergic reaction, what symptoms look like and what treatments can calm such a reaction.
Disease
Dry eyes
Eyes feeling dry and uncomfortable? Inadequate tear production is a common — and very treatable — eye condition. Find out what causes it and how to relieve symptoms.
Disease
Dry macular degeneration
Blurred or reduced central vision could be a sign of macular degeneration. Find out about symptoms and treatment for this common eye disorder.
Disease
Dry mouth
With this condition, also known as xerostomia, the salivary glands in the mouth don't make enough saliva to keep the mouth wet.
Disease
Dry skin
Learn more about the causes of and self-care tips for a common flaky skin condition that tends to be temporary or seasonal but may become a lifelong problem.
Disease
Dry socket
This painful condition can happen after tooth removal. A blood clot where the tooth was removed does not form, comes out or dissolves before wound healing.
Disease
Ductal carcinoma in situ (DCIS)
Noninvasive breast cancer often has no symptoms. Find out about the causes, diagnosis and treatment of this form of breast cancer.
Disease
Dumping syndrome
People who have had stomach or weight-loss surgery can develop dumping syndrome, which causes cramping, diarrhea and, sometimes, low blood sugar.