July 6, 2008



Drug Dependence & Abuse Glossary of Medical Terms

These are medical definitions of medical terms from the MedTerms.com medical dictionary that appear in the Drug Dependence & Abuse article.

Abdominal: Relating to the abdomen, the belly , that part of the body that contains all of the structures between the chest and the pelvis . The abdomen is separated anatomically from the chest by the diaphragm , the powerful muscle spanning the body cavity below the lungs .
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Abdominal pain: Pain in the belly (the abdomen). Abdominal pain can come from conditions affecting a variety of organs. The abdomen is an anatomical area that is bounded by the lower margin of the ribs above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although abdominal pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (the skin and abdominal wall muscles), the term abdominal pain generally is used to describe pain originating from organs within the abdominal cavity (from beneath the skin and muscles). These organs include the stomach, small intestine, colon, liver, gallbladder, and pancreas.
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Abnormal: Not normal. Deviating from the usual structure, position, condition, or behavior. In referring to a growth, abnormal may mean that it is cancerous or premalignant (likely to become cancer ).
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Absorption: Uptake. In the biomedical sciences, absorption has diverse specific meanings.
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Acute: Of abrupt onset, in reference to a disease. Acute often also connotes an illness that is of short duration, rapidly progressive, and in need of urgent care.
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Addiction: A chronic relapsing condition characterized by compulsive drug-seeking and abuse and by long-lasting chemical changes in the brain . Addiction is the same irrespective of whether the drug is alcohol , amphetamines, cocaine , heroin , marijuana , or nicotine . Every addictive substance induces pleasant states or relieves distress. Continued use of the addictive substance induces adaptive changes in the brain that lead to tolerance, physical dependence, uncontrollable craving and, all too often, relapse . Dependence is at such a point that stopping is very difficult and causes severe physical and mental reactions from withdrawal. The risk of addiction is in part inherited. Genetic factors, for example, account for about 40% of the risk of alcoholism . The genetic factors predisposing to addiction are not yet fully understood.
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Alcohol: An organic chemical in which one or more hydroxyl (OH) groups are attached to carbon (C) atoms in place of hydrogen (H) atoms. Common alcohols include ethyl alcohol or ethanol (found in alcoholic beverages), methyl alcohol or methanol (can cause blindness) and propyl alcohol or propanol (used as a solvent and antiseptic ). Rubbing alcohol is a mixture of acetone , methyl isobutyl ketone, and ethyl alcohol. In everyday talk, alcohol usually refers to ethanol as, for example, in wine, beer, and liquor. It can cause changes in behavior and be addictive.
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Alcoholics Anonymous: A free, self-help organization founded to assist people addicted to alcohol in breaking old behavior patterns and gaining support for living a sober lifestyle.
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Amphetamine: A drug with a stimulant effect on the central nervous system that can be both physically and psychologically addictive when overused. This drug has been much abused recreationally. The street term " speed " refers to stimulant drugs such as amphetamine.
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Benzodiazepines: A class of drugs that act as tranquilizers and are commonly used in the treatment of anxiety. Benzodiazepines can cause drowsiness.
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Blood: The familiar red fluid in the body that contains white and red blood cells , platelets , proteins , and other elements. The blood is transported throughout the body by the circulatory system . Blood functions in two directions: arterial and venous. Arterial blood is the means by which oxygen and nutrients are transported to tissues while venous blood is the means by which carbon dioxide and metabolic by-products are transported to the lungs and kidneys, respectively, for removal from the body.
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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 ".
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Bowel: Another name for the intestine . The small bowel and the large bowel are the small intestine and large intestine , respectively.
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Brain: That part of the central nervous system that is located within the cranium ( skull ). The brain functions as the primary receiver, organizer and distributor of information for the body. It has two (right and left) halves called "hemispheres."
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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.
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Cancer: An abnormal growth of cells which tend to proliferate in an uncontrolled way and, in some cases, to metastasize (spread).
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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 .
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Chest pain: There are many causes of chest pain. One is angina which results from inadequate oxygen supply to the heart muscle. Angina can be caused by coronary artery disease or spasm of the coronary arteries. Chest pain can also be due to a heart attack (coronary occlusion) and other important diseases such as, for example, dissection of the aorta and a pulmonary embolism . Do not try to ignore chest pain and "work (or play) though it." Chest pain is a warning to seek medical attention.
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Chronic: This important term in medicine comes from the Greek chronos, time and means lasting a long time.
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Chronic pain : Pain (an unpleasant sense of discomfort) that persists or progresses over a long period of time. In contrast to acute pain that arises suddenly in response to a specific injury and is usually treatable, chronic pain persists over time and is often resistant to medical treatments.
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Cocaine: The most potent stimulant of natural origin, a bitter addictive anesthetic (pain blocker) which is extracted from the leaves of the coca scrub (Erythroxylon coca) indigenous to the Andean highlands of South America.
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Coma: A state of deep unarousable unconsciousness.
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Condition: The term "condition" has a number of biomedical meanings including the following:

  1. An unhealthy state, such as in "this is a progressive condition."
  2. A state of fitness, such as "getting into condition."
  3. Something that is essential to the occurrence of something else; essentially a "precondition."
  4. As a verb: to cause a change in something so that a response that was previously associated with a certain stimulus becomes associated with another stimulus; to condition a person, as in behavioral conditioning.

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Depression : An illness that involves the body, mood, and thoughts, that affects the way a person eats and sleeps, the way one feels about oneself, and the way one thinks about things. A depressive disorder is not the same as a passing blue mood. It is not a sign of personal weakness or a condition that can be wished away. People with a depressive disease cannot merely "pull themselves together" and get better. Without treatment, symptoms can last for weeks, months, or years. Appropriate treatment, however, can help most people with depression.
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Detox: Short for detoxification, usually from an addictive drug such as alcohol or heroin . A detox center is designed to promote the recovery of a person from an addiction .
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Diarrhea : A familiar phenomenon with unusually frequent or unusually liquid bowel movements, excessive watery evacuations of fecal material. The opposite of constipation . The word "diarrhea" with its odd spelling is a near steal from the Greek "diarrhoia" meaning "a flowing through." Plato and Aristotle may have had diarrhoia while today we have diarrhea. There are myriad infectious and noninfectious causes of diarrhea.
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Discharge: 1.The flow of fluid from part of the body, such as from the nose or vagina.
2. The passing of an action potential, such as through a nerve or muscle fiber .
3. The release of a patient from a course of care. The doctor may then dictate a discharge summary.
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Emergency department: The department of a hospital responsible for the provision of medical and surgical care to patients arriving at the hospital in need of immediate care. Emergency department personnel may also respond to certain situations within the hospital such cardiac arrests.
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Essential: 1. Something that cannot be done without.
2. Required in the diet, because the body cannot make it. As in an essential amino acid or an essential fatty acid.
3. Idiopathic. As in essential hypertension. "Essential" is a hallowed term meaning "We don't know the cause."
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Fetus: The unborn offspring from the end of the 8th week after conception (when the major structures have formed) until birth. Up until the eighth week, the developing offspring is called an embryo.
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Hallucinogenic: 1. As an adjective: Producing hallucinations . From hallucino- + -genic, a word ending meaning producing. 2. As a noun: A drug that induces hallucinations. (This is incorrect usage; the noun is hallucinogen .)
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Heart: The muscle that pumps blood received from veins into arteries throughout the body. It is positioned in the chest behind the sternum (breastbone; in front of the trachea, esophagus, and aorta; and above the diaphragm muscle that separates the chest and abdominal cavities. The normal heart is about the size of a closed fist, and weighs about 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 chest.
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Hepatitis: Inflammation of the liver from any cause.
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Heroin: Semisynthetic drug derived from morphine. Discovered in 1874, it was introduced commercially in 1898 by the Bayer company in Germany. The name heroin was coined from the German heroisch meaning heroic, strong. Heroin is stronger (more potent) than morphine.
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HIV: Acronym for the Human Immunodeficiency Virus , the cause of AIDS (acquired immunodeficiency syndrome). HIV has also been called the human lymphotropic virus type III, the lymphadenopathy-associated virus and the lymphadenopathy virus . No matter what name is applied, it is a retrovirus. (A retrovirus has an RNA genome and a reverse transcriptase enzyme. Using the reverse transcriptase , the virus uses its RNA as a template for making complementary DNA which can integrate into the DNA of the host organism).
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Hospital: It may seem unnecessary to define a "hospital" since everyone knows the nature of a hospital. A hospital began as a charitable institution for the needy, aged, infirm, or young.
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Impotence : A common problem among men characterized by the consistent inability to sustain an erection sufficient for sexual intercourse or the inability to achieve ejaculation , or both. Impotence can vary. It can involve a total inability to achieve an erection or ejaculation, an inconsistent ability to do so, or a tendency to sustain only very brief erections.
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Laboratory: A place for doing tests and research procedures and preparing chemicals, etc. Although "laboratory" looks very like the Latin "laboratorium" (a place to labor, a work place), the word "laboratory" came from the Latin "elaborare" (to work out, as a problem, and with great pains), as evidenced by the Old English spelling "elaboratory" designating "a place where learned effort was applied to the solution of scientific problems."
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Marijuana: A very common street and recreational drug that comes from the marijuana plant.
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Medication: 1. A drug or medicine. 2. The administration of a drug or medicine. (Note that "medication" does not have the dangerous double meaning of "drug.")
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Metabolism: The whole range of biochemical processes that occur within us (or any living organism). Metabolism consists both of anabolism and catabolism (the buildup and breakdown of substances, respectively). The term is commonly used to refer specifically to the breakdown of food and its transformation into energy.
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Mouth: 1. The upper opening of the digestive tract, beginning with the lips and containing the teeth, gums, and tongue. Foodstuffs are broken down mechanically in the mouth by chewing and saliva is added as a lubricant. Saliva contains amylase, an enzyme that digests starch. 2. Any opening or aperture in the body. The mouth in both senses of the word is also called the os, the Latin word for an opening, or mouth. The o in os is pronounced as in hope. The genitive form of os is oris from which comes the word oral.
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Mucosa: Having to do with a mucous membrane. For example, the oral mucosa.
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Muscle: Muscle is the tissue of the body which primarily functions as a source of power. There are three types of muscle in the body. Muscle which is responsible for moving extremities and external areas of the body is called "skeletal muscle." Heart muscle is called "cardiac muscle." Muscle that is in the walls of arteries and bowel is called "smooth muscle."
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Nausea: Nausea, is the urge to vomit. It can be brought by many causes including, systemic illnesses, such as influenza , medications, pain, and inner ear disease. When nausea and/or vomiting are persistent, or when they are accompanied by other severe symptoms such as abdominal pain , jaundice , fever, or bleeding, a physician should be consulted.
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Nose: The external midline projection from the face.
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Onset: In medicine, the first appearance of the signs or symptoms of an illness as, for example, the onset of rheumatoid arthritis . There is always an onset to a disease but never to the return to good health. The default setting is good health.
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Organ: A relatively independent part of the body that carries out one or more special functions. The organs of the human body include the eye , ear , heart , lungs , and liver .
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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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PCP: Pneumocystis carinii pneumonia . A parasitic infection of the lungs that is particularly common and life-threatening in immunosuppressed persons. Prophylaxis is available to prevent PCP.
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Pharmacy: A location where prescription drugs are sold. A pharmacy is, by law, constantly supervised by a licensed pharmacist.
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Poison: Any substance that can cause severe distress or death if ingested, breathed in, or absorbed through the skin. Many substances that normally cause no problems, including water and most vitamins , can be poisonous if taken in too large of a quantity. Poison treatment depends on the substance: if there are treatment instructions on the substance's container and you are sure it contained no other item, follow those directions immediately. Always contact your nearest Poison Control Center if you are concerned about possible poison ingestion.
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Pregnant: The state of carrying a developing fetus within the body.
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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.
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Psychiatric: Pertaining to or within the purview of psychiatry , the medical specialty concerned with the prevention, diagnosis , and treatment of mental illness.
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Pulse: The rhythmic contraction and expansion of an artery due to the surge of blood from the beat of the heart. The pulse is most often measured by feeling the arteries of the wrist. There is also a pulse, although far weaker, in veins.
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Rape: Forced sexual intercourse; sexual assault; sexual intercourse between an adult and a minor . Rape may be heterosexual (involving members of opposite sexes) or homosexual (involving members of the same sex). Rape involves insertion of an erect penis or an inanimate object into the female vagina or the male anus . Legal definitions of rape may also include forced oral sex and other sexual acts.
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Referral: The recommendation of a medical or paramedical professional. If you get a referral to ophthalmology, for example, you are being sent to the eye doctor. In HMOs and other managed care schemes, a referral is usually necessary to see any practitioner or specialist other than your primary care physician (PCP), if you want the service to be covered. The referral is obtained from your PCP, who may require a telephone or office consultation first.
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Relapse: The return of signs and symptoms of a disease after a patient has enjoyed a remission . For example, after treatment a patient with cancer of the colon went into remission with no sign or symptom of the tumor, remained in remission for 4 years, but then suffered a relapse and had to be treated once again for colon cancer.
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Respiratory: Having to do with respiration, the exchange of oxygen and carbon dioxide. From the Latin re- (again) + spirare (to breathe) = to breathe again.
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Respiratory rate: The number of breaths per minute or, more formally, the number of movements indicative of inspiration and expiration per unit time. In practice, the respiratory rate is usually determined by counting the number of times the chest rises or falls per minute. By whatever means, the aim is to determine if the respirations are normal, abnormally fast ( tachypnea ), abnormally slow (bradypnea), or nonexistent ( apnea ).
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Sense: In biology and medicine, the faculty of sensory reception. The ability to convey specific types of external or internal stimuli to the brain and perceive them. Sensory reception occurs through a process known as transduction in which stimuli are converted into nerve impulses which are relayed to the brain.
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Sign: Any objective evidence of disease. Gross blood in the stool is a sign of disease. It can be recognized by the patient, doctor, nurse, or others. In contrast, a symptom is, by its nature, subjective. Abdominal pain is a symptom. It is something only the patient can know.
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Skin: The skin is the body's outer covering. It protects us against heat and light, injury, and infection. It regulates body temperature and stores water, fat, and vitamin D. Weighing about 6 pounds, the skin is the body's largest organ. It is made up of two main layers; the outer epidermis and the inner dermis.


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Sleep : The body's rest cycle.
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Snort: Take in a drug by inhalation. For example, snorting cocaine is inhaling cocaine powder through the nose where it is absorbed through the nasal tissues into the bloodstream.
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Stomach: 1. The sac-shaped digestive organ that is located in the upper abdomen, under the ribs. The upper part of the stomach connects to the esophagus, and the lower part leads into the small intestine.
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Substance: 1. Material with particular features, as a pressor substance .
2. The material that makes up an organ or structure. Also known in medicine as the substantia.
3. A psychoactive drug as, for example, in substance abuse .
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Substance abuse: The excessive use of a substance, especially alcohol or a drug. (There is no universally accepted definition of substance abuse.)
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Surgeon: A physician who treats disease, injury, or deformity by operative or manual methods. A medical doctor specialized in the removal of organs, masses and tumors and in doing other procedures using a knife (scalpel). The definition of a "surgeon" has begun to blur in recent years as surgeons have begun to minimize the cutting, employ new technologies that are "minimally invasive," use scopes, etc.
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Surgeon General: In the United States, the chief medical officer of the U.S. Public Health Service (USPS), the agency responsible for the public health of the American people. The Public Health Service ( PHS ) administers a number of critically important health agencies including the Food and Drug Administration ( FDA ), the Centers for Disease Control ( CDC ), and the National Institutes of Health ( NIH ).
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Syndrome: A set of signs and symptoms that tend to occur together and which reflect the presence of a particular disease or an increased chance of developing a particular disease.
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Virus: A microorganism smaller than a bacteria, which cannot grow or reproduce apart from a living cell. A virus invades living cells and uses their chemical machinery to keep itself alive and to replicate itself. It may reproduce with fidelity or with errors (mutations)-this ability to mutate is responsible for the ability of some viruses to change slightly in each infected person, making treatment more difficult.
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Vital: Necessary to maintain life. Breathing is a vital function.
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