Use the A-Z list to browse more than 6,000 health-related topics in our library. Clicking on a term opens the definition and, in most cases, links to more information.
"NHANES" is more commonly referred to as "National Health and Nutrition Examination Survey" in the medical community. National Health and Nutrition Examination Survey
A program overseen by the Centers for Disease Control and Prevention (CDC), designed to assess the health and nutritional status of Americans. Started in the 1960s, the survey combines information from interviews and physical exams.
"NHL" is more commonly referred to as "Non Hodgkin's Lymphoma" in the medical community. Non Hodgkin's Lymphoma
A group that includes any form of lymphoma (cancer of the lymph system) that does not behave in the predictable patterns associated with Hodgkin's disease. It is the sixth most common form of cancer in the United States. More Information on Non Hodgkin's Lymphoma: Lymphoma (Hodgkin's & Non)
"NHLBI" is more commonly referred to as "National Heart, Lung and Blood Institute" in the medical community. National Heart, Lung and Blood Institute
One of the National Institutes of Health, the NHLBI coordinates national priorities in the research of diseases related to the heart, blood vessels, blood and lungs, as well as sleep disorders. It performs research and funds others through grants.
"NIA" is more commonly referred to as "National Institute on Aging" in the medical community. National Institute on Aging
An organization that promotes a broad scientific effort to understand the nature of aging and to extend the healthy, active years of life. It is part of the federal government's National Institutes of Health (NIH).
"Niacin" is more commonly referred to as "Vitamin B3" in the medical community. Vitamin B3
A B vitamin that helps convert food into energy and maintains normal functioning of the skin, nerves and digestive system. It is found in meat, wheat germ, dairy products and yeast. Niacin may help prevent second heart attacks in some patients. More Information on Vitamin B3: Vitamins
A condition that results from a lack of niacin in the diet. It is marked by the "four Ds": diarrhea, dermatitis, dementia and death. It is rare in developed countries where balanced diets and fortified foods are common. More Information on Niacin Deficiency: Vitamins
A measure that includes preformed dietary niacin as well as niacin derived from tryptophan (an essential amino acid). Sixty milligrams of tryptophan yield about 1 milligram of niacin. More Information on Niacin Equivalents: Vitamins
"NIAID" is more commonly referred to as "National Institute of Allergy and Infectious Diseases" in the medical community. National Institute of Allergy and Infectious Diseases
Conducts and supports research to better understand, treat and prevent infectious, immunologic and allergic diseases.
A type of metal allergy caused by contact with nickel, a metal often used in earring posts. Nickel allergies may cause redness, rash, itching, swelling and other symptoms of contact dermatitis. More Information on Nickel Allergies: Cosmetic, Chemical & Metal
A coenzyme derived from the B vitamin niacin that becomes NADH when it accepts a pair of high-energy electrons for transport in cells. More Information on Nicotinamide Adenine Dinucleotide: Vitamins
A chemical found in tobacco that can act on the body either either as a stimulant or a depressant. It increases heart rate, blood pressure, the formation of blood clots, blood sugar and more, as well as altering moods. More Information on Nicotine: Smoking & Tobacco
Treatment to help patients stop smoking. The patient wears a patch that delivers nicotine through the skin and into the bloodstream. A new patch is worn each day on the upper body for a period of up to eight weeks or longer.
Therapy designed to deliver decreasing amounts of nicotine in a safe, nonaddictive form to help people quit smoking. Methods include a nicotine inhaler, nicotine gum, a nicotine patch or nicotine nasal spray. More Information on Nicotine Replacement Therapy: Smoking & Tobacco
Also Known As: "Time Release Niacin, Inositol Hexaniacinate, Extended Release Niacin, IHN"
A form of vitamin B3, or niacin, sometimes used in higher than normal doses for lowering triglycerides and increasing HDL cholesterol, and to a lesser degree, lowering LDL cholesterol. More Information on Nicotinic Acid: Cholesterol
"NIDDK" is more commonly referred to as "National Institute of Diabetes and Digestive and Kidney Diseases" in the medical community. National Institute of Diabetes and Digestive and Kidney Diseases
A division of the United States National Institutes of Health (NIH) that focuses on diabetes and endocrinology, as well as metabolic, digestive, kidney, urologic and hematologic diseases. It conducts and supports research in these areas.
"NIDDM" is more commonly referred to as "Type 2 Diabetes" in the medical community. Type 2 Diabetes
Also Known As: "Adult Onset Diabetes, Maturity Onset Diabetes, Noninsulin Dependent Diabetes Mellitus"
The most common form of diabetes. Patients manufacture insulin (sometimes more than necessary) but their bodies do not use it effectively. Its cause is unknown, but it is linked to age, obesity, family history, lack of exercise and other factors. More Information on Type 2 Diabetes: Type 2 Diabetes Basics
A group of inherited metabolic disorders known as the leukodystrophies in which lipids accumulate in the spleen, liver, lungs, bone marrow and brain. Symptoms include lack of muscle coordination and brain degeneration. More Information on Niemann Pick Disease: Birth & Genetic Disorders
Inability of the eyes to adjust to dim light or to regain vision quickly following a flash of bright light. More Information on Night Blindness: Eye Conditions
A device similar to an athletic mouth guard that is worn by patients who grind their teeth during sleep. It helps prevent jaw soreness and damage to the teeth. More Information on Night Guard: Tooth Decay & Damage
Also Known As: "Sleep Terrors, Sleep Terror Disorder"
A sleep disorder in which patients abruptly awaken from sleep in a terrified state during stage three and stage four sleep (deep sleep). The cause is unknown, but they are associated with periods of tension, stress or conflict. More Information on Night Terror Disorder: Sleep
Also Known As: "Night Terror Disorder, Sleep Terrors, Sleep Terror Disorder"
A sleep disorder in which patients abruptly awaken from sleep in a terrified state during stage three and stage four sleep (deep sleep). The cause is unknown, but they are associated with periods of tension, stress or conflict. More Information on Night Terrors: Sleep
Emotionally disturbing dreams that often occur during rapid eye movement (REM) sleep. Nightmares may provoke feelings of fear, terror, distress or extreme anxiety. They tend to occur in the latter part of the night and awaken the sleeper. More Information on Nightmare Disorder: Sleep
Emotionally disturbing dreams that often occur during rapid eye movement (REM) sleep. Nightmares may provoke feelings of fear, terror, distress or extreme anxiety. They tend to occur in the latter part of the night and awaken the sleeper. More Information on Nightmares: Sleep
Nightmares are emotionally disturbing dreams that often occur during rapid eye movement (REM) sleep. Night terrors are a sleep disorder in which patients abruptly awaken from sleep in a terrified state during deep sleep. More Information on Nightmares & Night Terrors: Sleep
"Nighttime Cough" is more commonly referred to as "Chronic Cough" in the medical community. Chronic Cough
Also Known As: "Morning Cough"
Coughing that occurs at night, in the early morning, with exercise or with exposure to cold air. It may indicate an allergy. More Information on Chronic Cough: Breathing & Lung
"Nighttime Hypoglycemia" is more commonly referred to as "Nocturnal Hypoglycemia" in the medical community. Nocturnal Hypoglycemia
Also Known As: "Overnight Hypoglycemia"
Low blood sugar (glucose) levels that occurs in the overnight hours when a patient is asleep. It may lead to symptoms such as insomnia, night sweats, restlessness or nightmares. More Information on Nocturnal Hypoglycemia: Glucose
"NIH" is more commonly referred to as "National Institutes of Health" in the medical community. National Institutes of Health
A federally funded medical research organization. The goal of the NIH is to acquire knowledge to help prevent, detect, diagnose and treat disease. Cancer research is conducted through the NIH's National Cancer Institute.
"NIMH" is more commonly referred to as "National Institute of Mental Health" in the medical community. National Institute of Mental Health
An organization that works to improve mental health through biomedical research on the mind, brain and behavior. It is part of the federal government's National Institutes of Health (NIH).
"NINDS" is more commonly referred to as "National Institute of Neurological Disorders and Stroke" in the medical community. National Institute of Neurological Disorders and Stroke
Part of the National Institutes of Health (NIH) that was founded in 1950 to conduct and support research on brain and nervous system disorders.
Also Known As: "Nipah Virus Encephalitis, Nipah Virus Infection, Nipah Virus Disease"
Infection with a member of the virus family Paramyxoviridae. It was initially isolated in 1999 in Malaysia and Singapore. Thought to be found in bats, it is transmitted to humans through pigs and can be fatal. More Information on Nipah Virus: Infectious Disease Basics
Also Known As: "Nipah Virus Encephalitis, Nipah Virus Infection"
Infection with a member of the virus family Paramyxoviridae. It was initially isolated in 1999 in Malaysia and Singapore. Thought to be found in bats, it is transmitted to humans through pigs and can be fatal. More Information on Nipah Virus Disease: Infectious Disease Basics
Also Known As: "Nipah Virus Infection, Nipah Virus Disease"
Infection with a member of the virus family Paramyxoviridae. It was initially isolated in 1999 in Malaysia and Singapore. Thought to be found in bats, it is transmitted to humans through pigs and can be fatal. More Information on Nipah Virus Encephalitis: Infectious Disease Basics
Also Known As: "Nipah Virus Disease, Nipah Virus Encephalitis"
Infection with a member of the virus family Paramyxoviridae. It was initially isolated in 1999 in Malaysia and Singapore. Thought to be found in bats, it is transmitted to humans through pigs and can be fatal. More Information on Nipah Virus Infection: Infectious Disease Basics
A type of fundoplication that involves the 360-degree surgical wrapping of part of the stomach around the lower esophagus to create a new valve. More Information on Nissen Fundoplication: Digestive Treatments
Important nutrients for building protein. They can also be used as medications that relax the smooth muscles, such as those of the heart and blood vessels. Nitrates lower blood pressure and improve blood flow to the heart. More Information on Nitrates: Cholesterol
Also Known As: "Nitro-time, Nitroglyn, Nitro-Dur, Nitro-par, Nitrostat, Nitrong, Nitrocot"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitro-Bid: Heart Drug & Medication
Also Known As: "Nitro-par, Nitrostat, Nitrong, Nitrocot, Nitro-Bid, Nitro-time, Nitroglyn"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitro-Dur: Heart Drug & Medication
Also Known As: "Nitrostat, Nitrong, Nitrocot, Nitro-Bid, Nitro-time, Nitroglyn, Nitro-Dur"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitro-par: Heart Drug & Medication
Also Known As: "Nitroglyn, Nitro-Dur, Nitro-par, Nitrostat, Nitrong, Nitrocot, Nitro-Bid"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitro-time: Heart Drug & Medication
Also Known As: "Nitro-Bid, Nitro-time, Nitroglyn, Nitro-Dur, Nitro-par, Nitrostat, Nitrong"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitrocot: Heart Drug & Medication
A colorless, nonmetallic element that is tasteless and odorless. It is a living part of all tissues and is essential for the plant and animal growth. It is used in manure and chemical fertilizer, but can become a pollutant when used in excess.
The relationship between nitrogen taken into the body (typically as food) and the amount of nitrogen excreted from the body in urine and feces. A negative balance means parts of the body are breaking down faster than they are replaced. More Information on Nitrogen Balance: Nutrition Basics
Also Known As: "Nitro-time, Nitroglyn, Nitro-Dur, Nitro-par, Nitrostat, Nitrong, Nitrocot, Nitro-Bid"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitroglycerin: Heart Drug & Medication
Also Known As: "Nitro-Dur, Nitro-par, Nitrostat, Nitrong, Nitrocot, Nitro-Bid, Nitro-time"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitroglyn: Heart Drug & Medication
Also Known As: "Nitrocot, Nitro-Bid, Nitro-time, Nitroglyn, Nitro-Dur, Nitro-par, Nitrostat"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitrong: Heart Drug & Medication
Also Known As: "Nitrong, Nitrocot, Nitro-Bid, Nitro-time, Nitroglyn, Nitro-Dur, Nitro-par"
A type of nitrate, medications that relax the smooth muscles, most notably those of the heart and blood vessels. This lowers blood pressure, improves blood flow to the heart and reduces the heart's need for oxygen. More Information on Nitrostat: Heart Drug & Medication
A blend of two gases, oxygen and nitrogen, that has a calming effect when inhaled and absorbed by the body. It is typically used to calm nervous children during dental visits and is considered to be very safe. More Information on Nitrous Oxide: Oral Medications
"NKHH" is more commonly referred to as "Hyperosmolar Hyperglycemic Nonketotic Syndrome" in the medical community. Hyperosmolar Hyperglycemic Nonketotic Syndrome
Also Known As: "Hyperosmolar Hyperglycemic Nonketotic State, HHNS, Hyperglycemic Hyperosmolar State, Nonketosis Hyperosmolar Hyperglycemia, HHS"
A dangerous condition in which a person experiences very high glucose (blood sugar) and dehydration. Left untreated, it can lead to seizures, coma or death. More Information on Hyperosmolar Hyperglycemic Nonketotic Syndrome: Glucose
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