memantine, Namenda, Namenda XR Glossary of TermsThe following are health and medical definitions of terms that appear in the memantine, Namenda, Namenda XR article.
Acetylcholine: A neurotransmitter released by nerves that is essential for communication between the nerves and muscles. Acetylcholinesterase: An enzyme that breaks down the neurotransmitter acetylcholine at the synaptic cleft (the space between two nerve cells) so the next nerve impulse can be transmitted across the synaptic gap. Pesticides of the organophosphate and carbamate types act to paralyze and kill insects by inhibiting their acetylcholinesterase. Abbreviated AChE. Alzheimer's disease: A progressive degenerative disease of the brain that leads to dementia. On a cellular level, Alzheimer's disease is characterized by the finding of unusual helical protein filaments in nerve cells of the brain. These twisted filaments are called neurofibrillary tangles. In the brain, Alzheimer's disease involves degeneration of the cortical regions, especially the frontal and temporal lobes. There is currently no cure for Alzheimer's disease, but new medications and therapies appear to slow its progress and improve the patient's ability to function. Back pain: Pain felt in the low or upper back. Causes of pain in the low and upper back include conditions affecting the bony spine; discs between the vertebrae; ligaments around the spine and discs; spinal inflammation; spinal cord and nerves; muscles; internal organs of the pelvis, chest, and abdomen; tumors; and the skin. Bicarbonate: In medicine, bicarbonate usually refers to bicarbonate of soda (sodium bicarbonate, baking soda), a white powder that is a common ingredient in antacids. Also, the bicarbonate level is an indirect measure of the acidity of the blood that is determined when electrolytes are tested. The normal serum range for bicarbonate is 22'30 mmol/liter. Blood pressure: The blood pressure is the pressure of the blood within the arteries. It is produced primarily by the contraction of the heart muscle. It's measurement is recorded by two numbers. The first (systolic pressure) is measured after the heart contracts and is highest. The second (diastolic pressure) is measured before the heart contracts and lowest. A blood pressure cuff is used to measure the pressure. Elevation of blood pressure is called "hypertension". 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. Capsule: Capsule has many meanings in medicine including the following:
See the entire definition of Capsule Constipation: Infrequent and frequently incomplete bowel movements. Constipation is the opposite of diarrhea and is commonly caused by irritable bowel syndrome (IBS), diverticulosis, and medications. Paradoxically, constipation can also be caused by overuse of laxatives. Colon cancer can also narrow the colon and thereby cause constipation. A high-fiber diet can frequently relieve constipation. If the diet is not helpful, medical evaluation is warranted. Dementia: Significant loss of intellectual abilities, such as memory capacity, that is severe enough to interfere with social or occupational functioning. Criteria for the diagnosis of dementia include impairment of attention, orientation, memory, judgment, language, motor and spatial skills, and function. By definition, dementia is not due to major depression or schizophrenia. Alzheimer's disease is the most common cause of dementia. Other causes include AIDS, alcoholism, brain injury, vascular dementia (damage to the blood vessels leading to the brain), dementia with Lewy bodies, brain tumors, drug toxicity, infection of brain, Creutzfeldt-Jakob disease, meningitis, Pick disease, syphilis, and hypothyroidism. Dextromethorphan: An oral cough suppressant available in the US without a prescription but which is sometimes abused as a recreational drug. Dextromethorphan (DXM) is chemically related to codeine and acts on the brain to suppress cough, but it does not have the pain relieving and addictive properties of codeine. DXM is an ingredient in more than 125 nonprescription cough and cold medications, including forms of Robitussin, Coricidin and Vicks. Dizziness: Painless head discomfort with many possible causes including disturbances of vision, the brain, balance (vestibular) system of the inner ear, and gastrointestinal system. Dizziness is a medically indistinct term which laypersons use to describe a variety of conditions ranging from lightheadedness, unsteadiness to vertigo. Enzyme: A protein (or protein-based molecule) that speeds up a chemical reaction in a living organism. An enzyme acts as catalyst for specific chemical reactions, converting a specific set of reactants (called substrates) into specific products. Without enzymes, life as we know it would not exist. Fatigue: A condition characterized by a lessened capacity for work and reduced efficiency of accomplishment, usually accompanied by a feeling of weariness and tiredness. Fatigue can be acute and come on suddenly or chronic and persist. FDA: Food and Drug Administration. Fetus: An unborn offspring, from the embryo stage (the end of the eighth week after conception, when the major structures have formed) until birth. 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. Glutamate: A form of glutamic acid. See: Glutamic acid. Hallucination: A profound distortion in a person's perception of reality, typically accompanied by a powerful sense of reality. An hallucination may be a sensory experience in which a person can see, hear, smell, taste, or feel something that is not there. 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. Long-term memory: A system for permanently storing, managing, and retrieving information for later use. Items of information stored as long-term memory may be available for a lifetime. Memory: 1. The ability to recover information about past events or knowledge. 2. The process of recovering information about past events or knowledge. 3. Cognitive reconstruction. The brain engages in a remarkable reshuffling process in an attempt to extract what is general and what is particular about each passing moment. Nerve: A bundle of fibers that uses electrical and chemical signals to transmit sensory and motor information from one body part to another. The fibrous portions of a nerve are covered by a sheath called myelin and/or a membrane called neurilemma. (Note that entries for specific nerves can be found under the names of the particular nerves. For example, the optic nerve is not under 'nerve, optic' but rather under 'optic nerve.') Neurological: Having to do with the nerves or the nervous system as, for example, a neurological exam. Neurotransmitter: A chemical that is released from a nerve cell which thereby transmits an impulse from a nerve cell to another nerve, muscle, organ, or other tissue. A neurotransmitter is a messenger of neurologic information from one cell to another. 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. Offspring: The progeny, or young, born to a person. In a larger sense, the offspring are collectively all the descendants, the brood, or the family. For example, the offspring of someone with a genetic (inherited) condition, such as Huntington?s disease, are themselves at risk for the disease. 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. 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. Pregnant: The state of carrying a developing fetus within the body. 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. Receptor: 1. In cell biology, a structure on the surface of a cell (or inside a cell) that selectively receives and binds a specific substance. There are many receptors. There is a receptor for (insulin; there is a receptor for low-density lipoproteins (LDL); etc. To take an example, the receptor for substance P, a molecule that acts as a messenger for the sensation of pain, is a unique harbor on the cell surface where substance P docks. Without this receptor, substance P cannot dock and cannot deliver its message of pain. Variant forms of nuclear hormone receptors mediate processes such as cholesterol metabolism and fatty acid production. Some hormone receptors are implicated in diseases such as diabetes and certain types of cancer. A receptor called PXR appears to jump-start the body's response to unfamiliar chemicals and may be involved in drug-drug interactions. 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. Somnolence: Sleepiness, the state of feeling drowsy, ready to fall asleep. A person experiencing somnolence is somnolent and is acting somnolently. Stage: As regards cancer, the extent of a cancer, especially whether the disease has spread from the original site to other parts of the body. See also: Staging. Stevens-Johnson syndrome: A serious systemic (bodywide) allergic reaction with a characteristic rash involving the skin and mucous membranes, including the buccal mucosa (inside of the mouth), conjunctiva, and genital areas. Abbreviated SJS. The disease is due to a hypersensitive (allergic) reaction to one of a number of immunologic stimuli including drugs and infectious agents. Complications can include hepatitis, nephritis, gastrointestinal bleeding, pneumonia, arthritis, arthralgia, fever, and myalgia. The diagnosis of SJS is usually made when the characteristic rash appears 1 to 3 weeks after exposure to a known stimulus and it cannot be explained by another diagnosis. The treatment depends, in part, on the suspected precipitating cause. Also known as erythema multiforme. Syndrome: A combination of symptoms and signs that together represent a disease process. Urine: Liquid waste produced by the kidneys. Urine is a clear, transparent fluid that normally has an amber color. The average amount of urine excreted in 24 hours is between 5 to 8 cups or 40 and 60 ounces. Chemically, urine is mainly a watery solution of salt and substances called urea and uric acid. Normally, it contains about 960 parts water to 40 parts solid matter. Abnormally, it may contain sugar (in diabetes), albumin (a protein, as in some forms of kidney disease), bile pigments (as in jaundice), or abnormal quantities of one or another of its normal components. |
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