Health A-Z


Clinical Definition A decongestant is a medication that causes vasoconstriction of the blood vessels lining the nasal cavity or sinuses. This action may reduce tissue swelling and decrease congestion in the nose. Due to their vasoconstriction action, decongestants may cause hypertension as a side effect. In Our Own Words Decongestants are used to treat nasal

Deep Venous Thrombosis

Clinical Definition A deep venous thrombosis refers to a stationary blood clot, or thrombus formation, inside a vein. It usually develops in proximal veins of the lower extremities, and elements believed to contribute to thrombus formation include vascular injury, blood stasis and hypercoagulability. A pulmonary embolism is a serious complication of deep venous thrombosis. In


Clinical Definition A defibrillator is a medical device that can administer a therapeutic, electrical impulse to the myocardium of the heart. It is used to eradicate life-threatening arrhythmias and re-establish a normal contraction rhythm of the heart. In Our Own Words A defibrillator is a device used to deliver an electrical shock to the heart

Degenerative Disc Disease

Clinical Definition Degenerative disc disease is the deterioration of one or more of the intervertebral discs in a person’s spine. The condition reduces the disc’s ability to handle mechanical stress, such as twisting and bending, leading to back pain.  Aging, drying out and wear of a disc, which reduces the disc’s ability to absorb shock,


Clinical Definition Dehydration is a lack of adequate water in the body that can be hazardous and even life-threatening, often occurring due to inadequate fluid intake during hot weather, exercise, fever, diarrhea or vomiting. Older adults and those on diuretic medications for hypertension are also prone to dehydration.  Symptoms may include dry mouth, dry cough,


Clinical Definition Dementia is not a specific disease but a descriptive term for a collection of symptoms severe enough to interfere with daily life, such as a decline in memory, judgment or other thinking skills. These symptoms occur in many different disorders. Dementia is not a normal part of aging but is common in very


Clinical Definition Depression is characterized by a dejected mood and a cluster of other symptoms that persist throughout the majority of each day, in a time span of 2 weeks or more. These symptoms include five or more of the following tendencies: sleep changes, eating and appetite changes, low energy, poor concentration, agitation, slowness, thoughts


Clinical Definition Dermatitis is an umbrella term that describes an epidermal inflammation that can manifest as a range of skin irritations and rashes, ranging from mild to severe. In Our Own Words There are several common types of dermatitis (i.e., an irritation of the skin that can manifest in redness, irritation, itchiness and rashes), including


Clinical Definition Diarrhea is the frequent discharge of loose bowel movements consisting of semisolid or fluid fecal matter. Diarrhea has many potential causes and may be acute or chronic. In Our Own Words Diarrhea, sometimes called ”the runs,” is a watery, loose stool that can be a nuisance due to frequent trips to the toilet.


Clinical Definition A disinfectant is an agent used to destroy or inhibit the growth of pathogenic microorganisms. Most commonly, disinfectants are chemical substances used to prevent the spread of disease causing organisms. The disinfectant is typically applied to an inanimate object, such as a surgical tool. It differs from an antiseptic, which is applied to


Clinical Definition Diverticulitis is a condition that results when one or more diverticula become inflamed and infected. When the pouches become blocked with waste materials and bacterial buildup, the site then becomes inflamed and infected.  Cramps, abdominal tenderness, chills and fever can occur as the infection progresses. While the condition may resolve on its own,

Dry Eye

Clinical Definition Dry eye, or keratoconjunctivitis sicca, has a literal definition: dryness of the cornea and conjunctiva (i.e., the membrane covering outer eye surface). It occurs when the eyes don’t produce enough moisture, resulting in stinging, burning and irritation. Treatments ranging from artificial tears to surgery can relieve symptoms. In Our Own Words Dry eye,

Ductal Carcinoma In Situ

Clinical Definition Ductal carcinoma in situ, or DCIS, is non-invasive or pre-invasive breast cancer. Cells lining the ducts have developed the appearance of cancerous cells but have not invaded the ductal walls to surrounding breast tissues. The cure rate is high. In Our Own Words Ductal carcinoma in situ, or DCIS, is early stage breast


Clinical Definition The duodenum is the first part of the small intestine, located between the stomach and the jejunum. In Our Own Words The duodenum is the part of the small intestine where food mixes with stomach acids and other digestive juices (bile) from the pancreas and stomach. Your body absorbs vitamins, minerals and macro-nutrients


Clinical Definition Dyslexia is a neurologically based learning disorder, which impairs comprehension and processing of written language. Dyslexia usually is characterized by difficulty with spelling, phonological processing and fluent and accurate recognition of words. Although intelligence level is usually normal, the ability to read is impaired. In Our Own Words Dyslexia is a common learning


Clinical Definition Dyspepsia is a subjective feeling of pain or discomfort in the upper abdomen due to irritation of the stomach or processes involving the stomach. It can be acute or chronic, and treatment focuses on medications to reduce symptoms and mitigate the underlying causes, such as agents to reduce stomach acid or quell infections


Clinical Definition Dysplasia is the abnormal development or changes in cellular tissue which may be due to discrepancies in size, shape and organization of adult cells. A potential early indication of a neoplastic process, dysplasia is sometimes classified as either high or low grade, depending on the severity of cellular changes. In Our Own Words

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