levothyroxine sodium, Synthroid, Levoxyl, Levothroid, Unithroid Glossary of Terms

1. Hyperthyroidism Slideshow Pictures
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3. Thyroid Symptoms and Solutions Slideshow Pictures

Absorption: Uptake. For example, intestinal absorption is the uptake of food (or other substances) from the digestive tract.

Artery: A vessel that carries blood high in oxygen content away from the heart to the farthest reaches of the body. Since blood in arteries is usually full of oxygen, the hemoglobin in the red blood cells is oxygenated. The resultant form of hemoglobin (oxyhemoglobin) is what makes arterial blood look bright red.
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Atrial: Pertaining to the atria, the upper chambers of the heart, as in atrial fibrillation and atrial septal defect.

Atrial fibrillation: An abnormal and irregular heart rhythm in which electrical signals are generated chaotically throughout the upper chambers (atria) of the heart. Many people with atrial fibrillation have no symptoms. Among those who do, the most common symptom is an uncomfortable awareness of the rapid and irregular heartbeat (palpitations). Atrial fibrillation can promote the formation of blood clots that travel from the heart to the brain, resulting in stroke. Treatment of atrial fibrillation involves risk-factor control, use of medications to slow the heart rate and/or convert the heart to
normal rhythm, and prevention of blood clots. Also known as auricular fibrillation.

Brain: The portion of the central nervous system that is located within the skull. It functions as a primary receiver, organizer, and distributor of information for the body. It has a right half and a left half, each of which is called a hemisphere.

Breathing: The process of respiration, during which air is inhaled into the lungs through the mouth or nose due to muscle contraction and then exhaled due to muscle relaxation.

Cardiovascular: Relating to the circulatory system, which comprises the heart and blood vessels and carries nutrients and oxygen to the tissues of the body and removes carbon dioxide and other wastes from them. Cardiovascular diseases are conditions that affect the heart and blood vessels and include arteriosclerosis, coronary artery disease, heart valve disease, arrhythmia, heart failure, hypertension, orthostatic hypotension, shock, endocarditis, diseases of the aorta and its branches, disorders of the peripheral vascular system, and congenital heart disease.

Cardiovascular disease: Disease affecting the heart or blood vessels.
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Chest: The area of the body located between the neck and the abdomen. The chest contains the lungs, the heart, and part of the aorta. The walls of the chest are supported by the dorsal vertebrae, the ribs, and the sternum. Also known as thorax.

Chest pain: Pain in the chest that can be a result of many things, including angina, heart attack (coronary occlusion), and other important diseases. Chest pain is a warning to seek medical attention, so one should try not to ignore chest pain and 'work through it.'

Diarrhea: A common condition that involves unusually frequent and liquid bowel movements. The opposite of constipation. There are many infectious and noninfectious causes of diarrhea. Persistent diarrhea is both uncomfortable and dangerous to the health because it can indicate an underlying infection and may mean that the body is not able to absorb some nutrients due to a problem in the bowels. Treatment includes drinking plenty of fluids to prevent dehydration and taking over-the-counter remedies. People with diarrhea that persists for more than a couple days, particularly small children or elderly people, should seek medical attention.

Epinephrine: A substance produced by the medulla (inside) of the adrenal gland. The name epinephrine was coined in 1898 by the American pharmacologist and physiologic chemist (biochemist) John Jacob Abel who isolated it from the adrenal gland which is located above (epi-) the kidney ("nephros" in Greek). (Abel also crystallized insulin). Technically speaking, epinephrine is a sympathomimetic catecholamine. It causes quickening of the heart beat, strengthens the force of the heart's contraction, opens up the airways (bronchioles) in the lungs and has numerous other effects. The secretion of epinephrine by the adrenal is part of the fight-or-flight reaction. Adrenaline is a synonym of epinephrine and is the official name in the British Pharmacopoeia.

Euthyroid: The state of having normal thyroid gland function. As opposed to hyperthyroid (overactive thyroid) and hypothyroid (underactive thyroid).

Fetus: An unborn offspring, from the embryo stage (the end of the eighth week after conception, when the major structures have formed) until birth.

Fever: Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.).
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Fibrillation: In cardiology, an abnormal and erratic twitching of the heart muscle.

Generic: 1. The chemical name of a drug. 2. A term referring to the chemical makeup of a drug rather than to the advertised brand name under which the drug may be sold. 3.A term referring to any drug marketed under its chemical name without advertising.

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Gland: A group of cells that secrete a substance for use in the body. For example, the thyroid gland.

Headache: A pain in the head with the pain being above the eyes or the ears, behind the head (occipital), or in the back of the upper neck. Headache, like chest pain or back ache, has many causes.
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Heart: The muscle that pumps blood received from veins into arteries throughout the body. The heart is positioned in the chest behind the sternum (breastbone); in front of the trachea, esophagus, and aorta; and above the diaphragm. A normal heart is about the size of a closed fist and weighs about 298 grams or 10.5 ounces. It is cone-shaped, with the point of the cone pointing down to the left. Two-thirds of the heart lies in the left side of the chest, with the balance in the right side of the chest. The heart is composed of specialized cardiac muscle, and it is four-chambered, with a right atrium and ventricle, and an anatomically separate left atrium and ventricle. The blood flows from the systemic veins into the right atrium, thence to the right ventricle, from which it is pumped to the lungs and then returned into the left atrium, thence to the left ventricle, from which it is driven into the systemic arteries. The heart is thus functionally composed of two hearts: the right heart and the left heart. The right heart consists of the right atrium, which receives deoxygenated blood from the body, and the right ventricle, which pumps the deoxygenated blood to the lungs under low pressure; and the left heart, which consists of the left atrium, which receives oxygenated blood from the lung, and the left ventricle, which pumps the oxygenated blood out to the body under high pressure.

Heart attack: The death of heart muscle due to the loss of blood supply. The loss of blood supply is usually caused by a complete blockage of a coronary artery, one of the arteries that supplies blood to the heart muscle. Death of the heart muscle, in turn, causes chest pain and electrical instability of the heart muscle tissue.
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Heart failure: Inability of the heart to keep up with the demands on it and, specifically, failure of the heart to pump blood with normal efficiency. When this occurs, the heart is unable to provide adequate blood flow to other organs such as the brain, liver and kidneys. Heart failure may be due to failure of the right or left or both ventricles. The signs and symptoms depend upon which side of the heart is failing. They can include shortness of breath (dyspnea), asthma due to the heart (cardiac asthma), pooling of blood (stasis) in the general body (systemic) circulation or in the liver's (portal) circulation, swelling (edema), blueness or duskiness (cyanosis), and enlargement (hypertrophy) of the heart.
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Heart rate: The number of heartbeats per unit of time, usually per minute. The heart rate is based on the number of contractions of the ventricles (the lower chambers of the heart). The heart rate may be too fast (tachycardia) or too slow (bradycardia). The pulse is a bulge of an artery from waves of blood that course through the blood vessels each time the heart beats. The pulse is often taken at the wrist to estimate the heart rate.

Hormone: A chemical substance produced in the body that controls and regulates the activity of certain cells or organs. Many hormones are secreted by special glands, such as thyroid hormone produced by the thyroid gland. Hormones are essential for every activity of life, including the processes of digestion, metabolism, growth, reproduction, and mood control. Many hormones, such as neurotransmitters, are active in more than one physical process.

Hormone therapy: Treatment of disease or symptoms with synthetic or naturally derived hormones. The term is most commonly used to describe use of medications containing both estrogen and progestogen to reduce or stop short-term changes associated with the perimenopause. In the more general sense, hormone therapy may be used to treat some forms of cancer, taking advantage of the fact that certain cancers depend on hormones to grow. It may also be used for thyroid disorders, and illnesses associated with hormone production or use. Hormone therapy may include giving hormones to the patient or using medications that decrease the level of hormones in the body.

Hypothyroid: Deficiency of thyroid hormone which is normally made by the thyroid gland which is located in the front of the neck:

Insomnia: The perception or complaint of inadequate or poor-quality sleep due to a number of factors, such as difficulty falling asleep, waking up frequently during the night with difficulty returning to sleep, waking up too early in the morning, or unrefreshing sleep. Insomnia is not defined by the number of hours of sleep a person gets or how long it takes to fall asleep; it is a measure of satisfaction with sleep. Individuals vary normally in their need for and their satisfaction with sleep. Insomnia may cause problems during the day, such as tiredness, a lack of energy, difficulty concentrating, and irritability.

Insulin: A natural hormone made by the pancreas that controls the level of the sugar glucose in the blood. Insulin permits cells to use glucose for energy. Cells cannot utilize glucose without insulin.
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Levothyroxine: A synthetic thyroid hormone used as a thyroid hormone replacement drug (brand names include Levothroid, Levoxine, Levoxyl, Synthroid) used to treat an underactive thyroid gland (hypothyroidism).

Menstrual: Pertaining to menstruation (the menses), as in last menstrual period, menstrual cramps, menstrual cycle, and premenstrual syndrome. From the Latin menstrualis, from mensis meaning month.

Metabolic: Relating to metabolism, the whole range of biochemical processes that occur within us (or any living organism). Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances).
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Metabolism: The whole range of biochemical processes that occur within a living organism. Metabolism consists of anabolism (the buildup of substances) and catabolism (the breakdown of substances). The term metabolism is commonly used to refer specifically to the breakdown of food and its transformation into energy.

Nursing: 1) Profession concerned with the provision of services essential to the maintenance and restoration of health by attending the needs of sick persons. 2) Feeding a infant at the breast.

Pain: An unpleasant sensation that can range from mild, localized discomfort to agony. Pain has both physical and emotional components. The physical part of pain results from nerve stimulation. Pain may be contained to a discrete area, as in an injury, or it can be more diffuse, as in disorders like fibromyalgia. Pain is mediated by specific nerve fibers that carry the pain impulses to the brain where their conscious appreciation may be modified by many factors.
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Pregnancy: The state of carrying a developing embryo or fetus within the female body. This condition can be indicated by positive results on an over-the-counter urine test, and confirmed through a blood test, ultrasound, detection of fetal heartbeat, or an X-ray. Pregnancy lasts for about nine months, measured from the date of the woman's last menstrual period (LMP). It is conventionally divided into three trimesters, each roughly three months long.
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Prescription: A physician's order for the preparation and administration of a drug or device for a patient. A prescription has several parts. They include the superscription or heading with the symbol "R" or "Rx", which stands for the word recipe (meaning, in Latin, to take); the inscription, which contains the names and quantities of the ingredients; the subscription or directions for compounding the drug; and the signature which is often preceded by the sign "s" standing for signa (Latin for mark), giving the directions to be marked on the container.

Pulse: The rhythmic dilation of an artery that results from beating of the heart. Pulse is often measured by feeling the arteries of the wrist or neck.

Sodium: The major positive ion (cation) in the fluid surrounding cells in the body. The chemical notation for sodium is Na+. When sodium is combined with chloride, the resulting substance is a crystal called table salt. Excess dietary sodium is largely excreted in the urine, but too much salt in the diet tends to increase the blood pressure. Too much or too little sodium in the blood (called hypernatremia or hyponatremia respectively) can cause cells to malfunction, and extremes can be fatal. Normal blood sodium level is 135'145 milliEquivalents/liter (mEq/L) or 135'145 millimoles/liter (mmol/L) in international units.

Sweating: The act of secreting fluid from the skin by the sweat (sudoriferous) glands. These are small tubular glands situated within and under the skin (in the subcutaneous tissue). They discharge by tiny openings in the surface of the skin.
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Therapy: The treatment of disease. Therapy is synonymous with treatment.

Thyroid: 1. The thyroid gland. Also, pertaining to the thyroid gland. 2. A preparation of the thyroid gland used to treat hypothyroidism. 3. Shaped like a shield. (The thyroid gland was so-named by Thomas Wharton in 1656 because it was shaped like an ancient Greek shield.)
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Thyroid gland: A gland that makes and stores hormones that help regulate the heart rate, blood pressure, body temperature, and the rate at which food is converted into energy. Thyroid hormones are essential for the function of every cell in the body. They help regulate growth and the rate of chemical reactions (metabolism) in the body. Thyroid hormones also help children grow and develop.
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Thyroid hormone: A chemical substance made by the thyroid gland for export into the bloodstream. The thyroid gland needs iodine to make thyroid hormones. The two most important thyroid hormones are thyroxine (T4) and triiodothyronine (T3).
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Thyroxine: A hormone that is made by the thyroid gland and is one of the most important thyroid hormones. Four iodine molecules are attached to the molecular structure of thyroxine. Along with the more powerful thyroid hormone triiodothyronine (T3), thyroxine affects almost every process in the body, including body temperature, growth, and heart rate. Also known as T4.

Toxicity: The degree to which a substance (a toxin or poison) can harm humans or animals. Acute toxicity involves harmful effects in an organism through a single or short-term exposure. Subchronic toxicity is the ability of a toxic substance to cause effects for more than one year but less than the lifetime of the exposed organism. Chronic toxicity is the ability of a substance or mixture of substances to cause harmful effects over an extended period, usually upon repeated or continuous exposure, sometimes lasting for the entire life of the exposed organism.

Warfarin: An anticoagulant drug (brand names: Coumarin, Panwarfin, Sofarin) taken to prevent the blood from clotting and to treat blood clots and overly thick blood. Warfarin is also used to reduce the risk of clots causing strokes or heart attacks.
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Weight loss: Weight loss is a decrease in body weight resulting from either voluntary (diet, exercise) or involuntary (illness) circumstances. Most instances of weight loss arise due to the loss of body fat, but in cases of extreme or severe weight loss, protein and other substances in the body can also be depleted. Examples of involuntary weight loss include the weight loss associated with cancer, malabsorption (such as from chronic diarrheal illnesses ), and chronic inflammation (such as with rheumatoid arthritis).