Day Care

Day care refers to the care provided for infants and toddlers, preschoolers, and school-aged children, either in their own homes, in the home of a relative or other caregiver, or in a center-based facility.

Death and Mourning

Mourning is the grieving process an individual experiences in response to the loss (often through death) of someone.


Decongestants are medicines used to relieve nasal congestion (stuffy nose).


Dehydration is the loss of water and salts that are essential for normal body function.

Dental Development

Dental development is the process by which children develop their first and second (permanent) teeth.

Dental Trauma

Dental trauma is injury to the teeth, gums, and jawbones. The most common dental trauma is a broken or displaced tooth.

Dependent Personality Disorder

Dependent personality disorder is a lack of self-confidence coupled with excessive dependence on others.

Depressive Disorders

Depression and depressive disorders (unipolar depression) are mental illnesses characterized by a profound and persistent feeling of sadness or despair and/or a loss of interest in things that once were pleasurable. Disturbance in sleep, appetite, and mental processes are common symptoms of depression.


Dermatitis is a general term used to describe inflammation of the skin.


Dermatomyositis is one of a group of relatively uncommon diseases known as inflammatory myopathies, or inflammatory disorders of the muscles. Dermatomyositis is distinguished from other diseases in this category by the fact that it causes a characteristic skin rash as well as affecting the strength and functioning of the muscles.

Development Tests

Development tests are tools that are used to help measure a child's developmental progress from infancy through adolescence.

Developmental Delay

A developmental delay is any significant lag in a child's physical, cognitive, behavioral, emotional, or social development, in comparison with norms.

Diabetes Mellitus

Diabetes mellitus is a chronic disease in which the body is not able to correctly process glucose for cell energy due to either an insufficient amount of the hormone insulin or a physical resistance to the insulin the body does produce. Without proper treatment through medication and/or lifestyle changes, the high blood glucose (or blood sugar) levels caused by diabetes can cause long-term damage to organ systems throughout the body.

Diaper Rash

Dermatitis of the buttocks, genitals, lower abdomen, or thigh folds of an infant or toddler is called diaper rash. The outside layer of skin normally forms a protective barrier that prevents infection; when the barrier fails, the child may develop a rash in the area covered by the diaper.


To most individuals, diarrhea means an increased frequency or decreased consistency of bowel movements; however, the medical definition is more exact than this. Diarrhea best correlates with an increase in stool weight; this increase is mainly due to excess water, which normally makes up 60 to 85 percent of fecal matter.

DiGeorge Syndrome

DiGeorge syndrome is a rare congenital disease that affects an infant's immune system and that is due to a large deletion from chromosome 22. The syndrome is marked by absence or underdevelopment of the thymus and parathyroid glands.


Diphtheria is a potentially fatal, contagious disease that usually involves the nose, throat, and air passages but may also infect the skin. Its most striking feature is the formation of a grayish membrane covering the tonsils and upper part of the throat.


The term "discipline" comes from the Latin word "disciplinare," which means "to teach." Many people, however, associate the word with punishment, which falls short of the full meaning of the word. Discipline, properly practiced, uses a multifaceted approach, including models, rewards, and punishments that teach and reinforce desired behavior.


More than 1 million children each year experience their parents' divorce. Less than 60 percent of American children live with both of their biological parents; about 25 percent live with their biological mother only; and about 4 percent live with their biological father only.


As a disorder, dizziness is classified into three categories: vertigo, syncope, and nonsyncope nonvertigo. Each category has its own set of symptoms, all related to the sense of balance.

Down Syndrome

Down syndrome is the most common cause of mental retardation and malformation in a newborn. A genetic disorder, it occurs because of the presence of an extra chromosome.


Children's drawings are visual representations made with crayons, markers, or pencils that are generated for pleasure but can also be used for therapeutic purposes or developmental assessment.

Drug Allergies/Sensitivities

A drug allergy is an adverse reaction to a medication, often an antibiotic, that is mediated by the body's immune system. A drug sensitivity is an unusual reaction to a drug that does not involve the immune system.

DTP Vaccine

DTP vaccine confers immunity to diphtheria, tetanus, and pertussis. The vaccine used in the United States is actually multiple diphtheria and tetanus toxoids combined with acellular pertussis (DTaP).

Duodenal Obstruction

Duodenal obstruction is a partial or complete obstruction of the duodenum, the first part of the small intestine. Obstruction prevents food from passing through the digestive tract, interfering with digestion and nutrition.


Dwarfism is a term applied broadly to a number of conditions resulting in unusually short stature.


Dyslexia is a learning disability characterized by problems in reading, spelling, writing, speaking, or listening. It results from the inability to process graphic symbols.


Dysmenorrhea refers to the pain or discomfort associated with menstruation. Although not a serious medical problem, the term describes a woman adolescent girl with menstrual symptoms severe enough to keep her from functioning for a day or two each month.