Site MapHelpFeedback

(See related pages)


abstinence  Refraining completely from the use of alcohol or another drug. Complete abstinence from alcohol means no drinking at all.
Abstinence syndrome  see withdrawal syndrome.
abstinence violation effect  The tendency of a person who has been abstaining (as from alcohol), and "slips," to go on and indulge fully, because the rule of abstinence has been broken.
acetaldehyde  The chemical product of the first step in the liver's metabolism of alcohol. It is normally present only in small amounts because it is rapidly converted to acetic acid.
acetylcholine  Neurotransmitter found in the parasympathetic branch and in the cerebral cortex.
acute  In general, "sharp." In medicine, "rapid." Referring to drugs, the short-term effects or effects of a single administration, as opposed to chronic, or long-term, effects of administration.
additive effects  When the effects of two different drugs add up to produce a greater effect than either drug alone. As contrasted with antagonistic effects, in which one drug reduces the effect of another, or synergistic effects, in which one drug greatly amplifies the effect of another.
adenosine  A chemical believed to be a neurotransmitter in the CNS, primarily at inhibitory receptors. Caffeine might act by antagonizing the normal action of adenosine on its receptors.
ADHD  Attention deficit hyperactivity disorder, a learning disability. Terminology of the DSM-IV.
affective disorder  A disorder of mood or emotion, in contrast to disorders of thought. Depression, mania, and bipolar (formerly manic-depressive) disorders are examples.
affective education  In general, education that focuses on emotional content or emotional reactions, in contrast to cognitive content. In drug education, one example is learning how to achieve certain "feelings" (of excitement or belonging to a group) without using drugs.
aftercare  In drug or alcohol treatment programs, the long-term follow-up or maintenance support that follows a more intense period of treatment.
AIDS  Acquired immunodeficiency syndrome, a disease in which the body's immune system breaks down, leading eventually to death. Because the disease is spread through the mixing of body fluids, it is more prevalent in intravenous drug users who share needles. The infectious agent is the human immunodeficiency virus (HIV).
alcohol  Generally refers to grain alcohol, or ethanol, as opposed to other types of alcohol (for example, wood or isopropyl alcohol), which are too toxic to be drinkable.
alcohol abuse  In the DSM-IV, defined as a pattern of pathological alcohol use that causes impairment of social or occupational functioning. Compare with alcohol dependence.
alcohol dehydrogenase  The enzyme that metabolizes almost all of the alcohol consumed by an individual. It is found primarily in the liver.
alcohol dependence  In the DSM-IV, alcohol dependence is considered a more serious disorder than alcohol abuse, in that dependence includes either tolerance or withdrawal symptoms.
alcoholic personality  Personality traits, such as immaturity and dependency, that are frequently found in alcoholics in treatment. Many of these consistent traits might be a result of years of heavy drinking rather than a cause of alcoholism.
Alcoholics Anonymous  A worldwide, loosely organized group of alcoholics who try to help each other abstain from the use of alcohol.
alcoholism  The word has many definitions and therefore is not a precise term. Definitions might refer to pathological drinking behavior (e.g., remaining drunk for two days), to impaired functioning (e.g., frequently missing work), or to physical dependence. See also alcohol abuse and alcohol dependence.
alternatives (to drugs)  Assuming that there are motives for drug use, such as the need to be accepted by a group, many prevention and treatment programs teach alternative methods for satisfying these motives.
Alzheimer's disease  A progressive neurological disease that occurs primarily in the elderly. It causes loss of memory and then progressively impairs more aspects of intellectual and social functioning. Large acetylcholine-containing neurons of the brain are damaged in this disease.
Amanita muscaria  The fly agaric mushroom, widely used in ancient times for its hallucinogenic properties.
amotivational syndrome  A hypothesized loss of motivation that has been attributed to chronic marijuana use.
anabolic  Promoting constructive metabolism; building tissue.
anabolic steroids  Substances that increase anabolic (constructive) metabolism, one of the functions of male sex hormones. The result is increased muscle mass.
analgesic  Pain-relieving. An analgesic drug produces a selective reduction of pain, whereas an anesthetic reduces all sensation.
anandamide  A naturally occurring brain chemical with marijuana-like properties.
androgenic  Masculinizing.
anesthetic  Sense-deadening. An anesthetic drug reduces all sensation, whereas an analgesic drug reduces pain.
angel dust  A street name for phencyclidine (PCP).
animism  The belief that objects and plants contain spirits that move and direct them.
Antabuse  Brand name for dusulfiram, a drug that interferes with the normal metabolism of alcohol, so that a person who drinks alcohol after taking disulfiram will become quite ill. Antabuse interferes with the enzyme aldehyde dehydrogenase, so that there is a buildup of acetaldehyde, the first metabolic product of alcohol.
antecedents  In the context of Chapter 1, behaviors or individual characteristics that can be measured before drug use and might therefore be somewhat predictive of drug use. These are not necessarily causes of the subsequent drug use.
anticonvulsant  A drug that prevents or reduces epileptic seizures.
antidepressant  A group of drugs used in treating depressive disorders. The MAO inhibitors, the tricyclics, and the SSRIs are the major examples.
antihistamines  A group of drugs that act by antagonizing the actions of histamine at its receptors. Used in cold and sinus remedies and in OTC sedatives and sleep aids.
anti-inflammatory  Reducing the local heat, swelling, and redness caused by injury or infection. Aspirin has anti-inflammatory properties.
antipsychotics  A group of drugs used to treat psychotic disorders, such as schizophrenia. Also called neuroleptics or major tranquilizers.
antipyretic  Fever-reducing. Aspirin is a commomly used antipyretic.
antitussive  Cough-reducing. Narcotics have this effect. OTC antitussives generally contain dextromethorphan.
anxiety disorders  Mental disorders characterized by excessive worry, fears, avoidance, or a sense of impending danger. At pathological levels, these disorders can be debilitating.
anxiolytics  Drugs, such as Valium, used in the treatment of anxiety disorders. Literally, "anxiety-dissolving."
aphrodisiac  Any substance that is said to promote sexual desire.
aspirin  Originally Bayer's brand name for acetylsalicylic acid, now a generic name for that chemical.
assassin  The story is that this term for a hired killer is derived from a hashish-using cult, the hashshiyya.
ataxia  Loss of coordinated movement; for example, the staggering gait of someone who has consumed a large amount of alcohol.
attention deficit hyperactivity disorder  A learning disability accompanied by hyperactivity. More common in male children. This DSM-IV diagnostic category replaces hyperkinetic syndrome and minimal brain dysfunction.
autonomic nervous system  The branch of the peripheral nervous system that regulates the visceral, or automatic, functions of the body, such as heart rate and intestinal motility. In contrast to the somatic, or voluntary, nervous system.
aversion therapy  A form of treatment that attempts to suppress an undesirable behavior by punishing each instance of the behavior. For example, the drinking of alcohol might be punished by electric shocks or by a drug that causes nausea.
BAC  Blood alcohol concentration, also called blood alcohol level (BAL). The proportion of blood that consists of alcohol. For example, a person with a BAC of 0.10 percent has alcohol constituting one-tenth of 1 percent of the blood and is legally intoxicated in all states.
balanced placebo  A research design in which alcohol is compared with a placebo beverage, and subjects either believe they are drinking alcohol or believe they are not.
barbiturate  A major class of sedative-hypnotic drugs, including amobarbital and sodium pentothal.
basal ganglia  A part of the brain containing large numbers of dopamine synapses. Responsible for maintaining proper muscle tone as a part of the extrapyramidal motor system. Damage to the basal ganglia, as in Parkinson's disease, produces muscular rigidity and tremors.
behavioral tolerance  Repeated use of a drug can lead to a diminished effect of the drug (tolerance). When the diminished effect occurs because the individual has learned to compensate for the effect of the drug, it is called behavioral tolerance. For example, a novice drinker might be unable to walk with a BAC of 0.20 percent, whereas someone who has practiced walking while intoxicated would be able to walk fairly well at the same BAC.
behavioral toxicity  Refers to the fact that a drug can be toxic because it impairs behavior and amplifies the danger level of many activities. The effect of alcohol on driving is an example.
benzodiazepine  The group of drugs that includes Valium (diazepam) and Librium (chlordiazepoxide). They are used as anxiolytics or sedatives, and some types are used as sleeping pills.
benzoylecgonine  A metabolite of cocaine that can be detected in urine samples.
bhang  A preparation of cannabis (marijuana) that consists of the whole plant, dried and powdered. The weakest of the forms commonly used in India.
binding  The interaction between a molecule and a receptor for that molecule. Although the molecules float onto and off the receptor, there are chemical and electrical attractions between a specific molecule and its receptor, so that there is a much higher probability that the receptor will be occupied by its proper molecule than by other molecules.
bioavailability  The availability of molecules of a drug at the site of the drug's action in the body. An important concept in comparing different brands of the same generic drug, because one preparation might dissolve better or be absorbed more readily than the other, thus producing greater bioavailability.
bipolar disorder  One of the major affective, or emotional, disorders. Periods of mania and periods of depression have occurred in the same individual. Also called manic-depressive illness.
blackout  A period of time during which a person was behaving, but of which the person has no memory. The most common cause of this phenomenon is excessive alcohol consumption, and blackouts are considered to indicate pathological drinking.
black tar  A type of illicit heroin usually imported from Mexico.
blood alcohol concentration  A measure of the concentration of alcohol in the blood, expressed in grams per 100 ml (percentage).
blood-brain barrier  Refers to the fact that many substances, including drugs, that can circulate freely in the blood do not readily enter the brain tissue. The major structural feature of this barrier is the tightly jointed epithelial cells lining blood capillaries in the brain. Drug molecules cannot pass between the cells but must instead go through their membranes. Small molecules and molecules that are lipid- (fat-) soluble cross the barrier easily. Obviously, all psychoactive drugs must be capable of crossing the blood-brain barrier.
brain stem  The medulla oblongata, pons, and midbrain. Located between the spinal cord and the forebrain, and generally considered to contain the "oldest" (in an evolutionary sense) and most primitive control centers for such basic functions as breathing, swallowing, and so on.
brand name  The name given to a drug by a particular manufacturer and licensed only to that manufacturer. For example, Valium is a brand name for diazepam. Other companies may sell diazepam, but Hoffman-LaRoche, Inc., owns the name Valium.
bright  Light-colored, flue-cured tobacco. Compare with burley.
British system  Generally refers to the fact that heroin addicts in Great Britain may register as addicts and be prescribed legal narcotics, including heroin.
burley  Dark-colored, air-cured tobacco. Compare with bright.
caffeinism  Habitual use of large amounts of caffeine, usually in coffee.
Camellia sinesis  The plant from which tea is made.
Cannabis  Genus of plants known as marijuana, or hemp. Includes C. indica and C. sativa.
carbon monoxide  A poisonous gas found in cigarette smoke.
catheter  A piece of plastic or rubber tubing that is inserted into a vein or other structure.
central nervous system  Brain and spinal cord.
charas  A preparation of cannabis, or marijuana, that is similar to hashish. The most potent form of marijuana commonly used in India.
chemical name  For a drug, the name that is descriptive of its chemical structure. For example, the chemical name sodium chloride is associated with the generic name table salt, of which there may be several brand names, such as Morton's.
China white  A street name for one of the potent synthetic narcotics.
chipper  An individual who uses heroin occasionally.
chronic  Occurring over time. Chronic drug use is long-term use; chronic drug effects are persistent effects produced by long-term use.
chronic obstructive lung disease  A group of disorders that includes emphysema and chronic bronchitis. Cigarette smoking is a major cause of these disorders.
cirrhosis  A serious, largely irreversible, and frequently deadly disease of the liver. Usually caused by chronic heavy alcohol use.
coca  The plant Erythroxylon coca, from which cocaine is derived. Also refers to the leaves of this plant.
cocaethylene  A potent stimulant formed when cocaine and alcohol are used together.
cocaine hydrochloride  The most common form of pure cocaine; it is stable and water soluble.
coca paste  A paste derived from the coca leaf in the process of making cocaine. It is sometimes smoked in South and Central America and Mexico.
codeine  A narcotic chemical present in opium.
coma  A state of unconsciousness from which the individual cannot be aroused.
congeners  In general, members of the same group. With respect to alcohol, the term refers to other chemicals that are produced in the process of making a particular alcoholic beverage.
controlled drinking  The concept that individuals who have been drinking pathologically can be taught to drink in a controlled, nonpathological manner.
controlled substance  A term coined for the 1970 federal law that revised previous laws regulating narcotics and dangerous drugs. Heroin and cocaine are examples of controlled substances.
correlate  A variable that is statistically related to some other variable, such as drug use.
crack  A smokable form of cocaine. Also called rock.
crank  Street name for illicitly manufactured methamphetamine.
crash  Originally referred to the rapid emotional descent after a binge of amphetamine use. One symptom is prolonged sleep, and eventually sleeping in general was referred to as crashing.
crystal meth  Street term for a form of methamphetamine crystals, also called ice.
cumulative effects  Drug effects that increase with repeated administrations, usually due to the buildup of the drug in the body.
DARE  Drug Abuse Resistance Education, the most popular prevention program in schools.
date-rape drug  A substance given to someone without her knowledge to cause unconsciousness in order to have nonconsensual sex. Rohypnol and GHB have become known for such use. A 1996 U.S. law provides serious penalties for using drugs in this manner.
Datura  A plant genus that includes many species used for their hallucinogenic properties. These plants contain anticholinergic chemicals.
DAWN  Drug Abuse Warning Network, a federal government system for reporting drug-related medical emergencies and deaths.
DEA  United States Drug Enforcement Administration.
delirium tremens  Alcohol withdrawal symptoms, including tremors and hallucinations.
demand reduction  Efforts to control drug use by reducing the demand for drugs, as opposed to efforts aimed at reducing the supply of drugs. Demand reduction efforts include education and prevention programs, as well as increased punishments for drug users.
depressant  Any of a large group of drugs that generally depress the CNS and at high doses induce sleep. Includes alcohol, the barbiturates, and other sedative-hypnotic drugs.
depression  A major type of mood disorder.
detoxification  The process of allowing the body to rid itself of a large amount of alcohol or another drug. Often the first step in a treatment program.
deviance  Behavior that is different from established social norms and that social groups take steps to change.
diagnosis  The process of identifying the nature of an illness. A subject of great controversy for mental disorders.
distillation  The process by which alcohol is separated from a weak alcohol solution to form more concentrated distilled spirits. The weak solution is heated, and the alcohol vapors are collected and condensed to a liquid form.
dopamine  A neurotransmitter found in the basal ganglia and other regions of the brain.
dose-response curve  A graph showing the relationship between the size of a drug dose and the size of the response (or the proportion of subjects showing the response).
drug  Any substance, natural or artificial, other than food, that by its chemical nature alters structure or function in the living organism.
drug abuse  The use of a drug in such a manner or in such amounts or in situations such that the drug use causes problems or greatly increases the chance of problems occurring.
drug disposition tolerance  The reduced effect of a drug, which can result from more rapid metabolism or excretion of the drug.
drug misuse  The use of prescribed drugs in greater amounts than, or for purposes other than, those prescribed by a physician or dentist.
drug therapy  The use of a drug in an effort to treat an illness.
DSM-IV  Diagnostic and Statistical Manual of Mental Disorders, fourth edition, published by the American Psychiatric Association. It has become a standard for naming and distinguishing among mental disorders.
dysentery  A bowel infection that causes severe diarrhea, pain, and fever.
Ecstasy  Street name for the hallucinogen MDMA. Also called "XTC."
ECT  Electroconvulsive therapy, or electroconvulsive shock treatment. A procedure in which an electrical current is passed through the head, resulting in an epileptic-like seizure. Although this treatment is now used infrequently, it is still considered to be the most effective and rapid treatment for severe depression.
ED50  The effective dose for half the subjects in a drug test.
effective dose  The dose of a drug that produces a certain effect in some percentage of the subjects. For example, an ED50 produces the effect in 50 percent of the subjects. Note that the dose will depend on the effect that is monitored.
EMIT  Enzyme multiplied immunoassay test. The most commonly used urine-screening technique for detecting the presence of various drugs.
emphysema  A lung disease in which tissue deterioration results in increased air retention and reduced exchange of gases. The result is difficulty breathing and shortness of breath. An example of a chronic obstructive lung disease, often caused by smoking.
employee assistance program  A program within a company or an organization that provides counseling and/or treatment services to employees.
endorphins  Opiate-like chemicals that occur naturally in the brains of humans and other animals. There are several proper endorphins, and the term is also used generically to refer to both the endorphins and the enkephalins.
enkephalins  Opiate-like chemicals that occur naturally in the brains of humans and other animals. The enkephalins are smaller molecules than the endorphins.
enzyme  A large, organic molecule that works to speed up a specific chemical reaction. Enzymes are found in brain cells, where they are needed for most steps in the synthesis of neurotransmitter molecules. They are also found in the liver, where they are needed for the metabolism of many drug molecules.
ephedrine  A drug derived from the Chinese medicinal herb ma huang and used to relieve breathing difficulty in asthma. A sympathomimetic from which amphetamine was derived.
epilepsy  A disorder of the nervous system in which recurring periods of abnormal electrical activity in the brain produce temporary malfunction. There might or might not be loss of consciousness or convulsive motor movements.
ergogenic  Energy-producing. Refers to drugs or other methods (e.g., blood doping) designed to increase an athlete's energy output.
ergotism  A disease caused by eating grain infected with the ergot fungus. There are both psychological and physical manifestations.
ethical  In pharmacy, medicines dispensed only by prescription.
expectancies  Learned beliefs about the effects of alcohol or another drug.
extrapyramidal system  A motor control system in the central nervous system that is responsible for maintaining muscle tone and posture. Parkinson's disease causes damage to this system. Antipsychotic drugs also interfere with the extrapyramidal system, often producing symptoms similar to those of Parkinson's disease.
false transmitter  One method by which a drug can affect the nervous system. The drug is taken into a neuron and acted on by enzymes to produce a substance resembling the natural neurotransmitter but differing from it functionally.
FAS  Fetal alcohol syndrome.
FDA  United States Food and Drug Administration.
fen-phen  A combination of two prescription weight-control medications, fenfluramine and phentermine. No longer prescribed, due to concerns with toxicity to heart valves.
fermentation  The process by which sugars are converted into grain alcohol through the action of yeasts.
fetal alcohol effect  Individual developmental abnormalities associated with the mother's alcohol use during pregnancy.
fetal alcohol syndrome  Facial and developmental abnormalities associated with the mother's alcohol use.
fibrocystic breast disease  A benign (noncancerous) but painful disorder characterized by lumps (fibrocysts) in the breasts. There is controversy as to whether caffeine consumption is related to this problem.
flashback  An experience reported by some users of LSD in which portions of the LSD experience recur at a later time without the use of the drug.
fly agaric mushroom  Amanita muscaria, a hallucinogenic mushroom that is also considered poisonous.
freebase  In general, when a chemical salt is separated into its basic and acidic components, the basic component is referred to as the free base. Most psychoactive drugs are bases that normally exist in a salt form. Specifically, the salt cocaine hydrochloride can be chemically extracted to form the cocaine free base, which is volatile and can therefore be smoked.
functional disorder  A mental disorder for which there is no known organic cause. Schizophrenia is a form of psychosis that is considered to be a functional disorder.
GABA  An inhibitory neurotransmitter; gamma-aminobutyric acid.
ganja  A preparation of cannabis (marijuana) in which the most potent parts of the plant are used.
gateway substances  Substances, such as alcohol, tobacco, and sometimes marijuana, that most users of illicit substances will have tried before their first use of cocaine, heroin, or other less widely used illicit drugs.
generic name  For drugs, a name that specifies a particular chemical without being chemically descriptive. As an example, the chemical name sodium chloride is associated with the generic name table salt, of which there may be several brand names, such as Morton's.
genetic marker  A chemical or physiological characteristic that is known to be caused by a particular gene and that is highly correlated with some disease state.
GRAE  "Generally recognized as effective"; a term defined by the FDA with reference to the ingredients found in OTC drugs (see also GRAS).
GRAHL  "Generally recognized as honestly labeled" (see also GRAE and GRAS).
grain neutral spirits  Ethyl alcohol distilled to a purity of 190 proof (95 percent).
grand mal  An epileptic seizure that results in convulsive motor movements and loss of consciousness.
GRAS  "Generally recognized as safe"; a term defined by the FDA with reference to food additives and the ingredients found in OTC drugs.
hallucinogen  A drug, such as LSD or mescaline, that produces profound alterations in perception.
hashish  A potent preparation of cannabis (marijuana).
hash oil  A slang term for oil of cannabis, a liquid extract from the marijuana plant.
henbane  A poisonous plant containing anticholinergic chemicals and sometimes used for its hallucinogenic properties. Hyoscyamus niger.
heroin  Originally Bayer's name for diacetylmorphine, a potent narcotic analgesic synthesized from morphine.
HIV  Human immunodeficiency virus. The infectious agent responsible for AIDS.
homeostasis  A state of physiological balance maintained by various regulatory mechanisms.
hormone  A chemical substance formed in one part of the body that stimulates action in another part of the body.
human growth hormone  A pituitary hormone responsible for some types of giantism.
hyperactive  Refers to a disorder characterized by short attention span and a high level of motor activity. The DSM-IV term is attention-deficit hyperactivity disorder.
hypnotic  Sleep-inducing. For drugs, refers to sleeping preparations.
hypodermic syringe  A device to which a hollow needle can be attached, so that solutions can be injected through the skin.
hypothalamus  A group of nuclei found at the base of the brain, just above the pituitary gland.
ibogaine  A hallucinogen that has been shown to reduce self-administration of cocaine and morphine in rats and is proposed to reduce craving in drug addicts.
ibuprofen  An aspirin-like analgesic and anti-inflammatory.
ice  The street name for crystals of methamphetamine hydrochloride.
immunoassay  A method for measuring an organic chemical by inducing an animal to develop an antibody to it, then purifying the antibody and using it to measure the chemical in another tissue sample.
IND  Approval to conduct clinical investigations on a new drug, filed with the FDA after animal tests are complete.
indole  A type of chemical structure. The neurotransmitter serotonin and the hallucinogen LSD both contain an indole nucleus.
inhalants  Any of a variety of volatile solvents or other products that can be inhaled to produce intoxication.
insomnia  Inability to sleep. The most common complaint is difficulty falling asleep. Often treated with a hypnotic drug.
interferon  A chemical produced by the body in response to viral infections. Interferon treatments have been shown to reduce the risk of catching a cold.
intramuscular  A type of injection in which the drug is administered into a muscle.
intravenous  A type of injection in which the drug is administered into a vein.
kretek  A clove cigarette.
laissez-faire  A theory that government should not interfere with business or other activities.
LD50  The lethal dose for half the animals in a test.
lethal dose  The dose of a drug that produces a lethal effect in some percentage of the animals on which it is tested. For example, LD50 is the dose that would kill 50 percent of the animals to which it was given.
leukoplakia  A whitening and thickening of the soft tissues of the mouth. The use of chewing tobacco is associated with an increase in leukoplakia, considered to be a "precancerous" tissue change.
limbic system  A system of various brain structures that are involved in emotional responses.
lipid solubility  The tendency of a chemical to dissove in oil, as opposed to in water.
lithium  A highly reactive metallic element, atomic number 3. Its salts are used in the treatment of mania and bipolar disorder.
liver microsomal enzyme  An enzyme associated with a particular subcellular component (the microsomal fraction) of liver cells. There are many such enzymes that are important for drug metabolism.
longitudinal  A study done over a period of time (months or years).
look-alikes  Drugs sold legally, usually through the mail, that are made to look like controlled, prescription-only drugs. The most common types contain caffeine and resemble amphetamine capsules or tablets.
ma huang  A Chinese herb containing ephedrine, which is a sympathomimetic drug from which amphetamine was derived.
major depression  A serious mental disorder characterized by a depressed mood. A specific diagnostic term in the DSM-IV.
malting  The process of wetting a grain and allowing it to sprout, to maximize its sugar content before fermentation to produce an alcoholic beverage.
mandrake  Mandragora officinarum, a plant having a branched root that contains anticholinergic chemicals. Now classed among the other anticholinergic hallucinogens, this plant was widely believed to have aphrodisiac properties.
marijuana  Also spelled marihuana; dried leaves of the cannabis plant.
MDMA  Methylenedioxy methamphetamine, a catechol hallucinogen related to MDA. Called "Ecstasy" or "XTC" on the street.
medial forebrain bundle  A group of neuron fibers that projects from the midbrain to the forebrain, passing near the hypothalamus. Now known to contain several chemically and anatomically distinct pathways, including dopamine and norepinephrine pathways.
medical model  With reference to mental disorders, a model that assumes that abnormal behaviors are symptoms resulting from a disease.
mental illness  A term that, to some theorists, implies acceptance of a medical model of mental disorders.
mesolimbic pathway  A group of dopamine-containing neurons that have their cell bodies in the midbrain and their terminals in the forebrain, on various structures associated with the limbic system. Believed by some theorists to be important in explaining the therapeutic effects of antipsychotic medications. Also believed by some theorists to be important for many types of behavioral reinforcers.
metabolism  (of drugs)The breakdown of drug molecules by enzymes, often in the liver.
metabolite  A product of enzyme action on a drug.
methadone maintenance  A program for treatment of narcotic addicts in which the synthetic drug methadone is provided to the addicts in an oral dosage form, so that they can maintain their addiction legally.
Mexican brown  A form of heroin that first appeared on American streets in the mid-1970s. Because the heroin is made from the hydrochloride salt of morphine, it is brown in its pure form.
moist snuff  A type of oral smokeless tobacco that is popular among young American men. A "pinch" of this chopped, moistened, flavored tobacco is held in the mouth, often between the lower lip and the gum.
monoamine oxidase (MAO) inhibitor  A drug that acts by inhibiting the enzyme monoamine oxidase (MAO). Used as an antidepressant.
morphinism  An older term used to describe dependence on the use of morphine.
motivational interviewing  A technique for encouraging alcoholics or addicts to seek treatment by first assessing their degree of dependence and then discussing the assessment results. Direct confrontation is avoided.
narcolepsy  A form of sleep disorder characterized by bouts of muscular weakness and falling asleep involuntarily. The most common treatment employs stimulant drugs such as amphetamine to maintain wakefulness during the day.
narcotic  See opiate.
narcotic antagonists  Drugs that can block the actions of narcotics.
Native American Church  A religious organization active among American Indians, in which the hallucinogenic peyote cactus is used in conjunction with Christian religious themes.
NDA  In FDA procedures, a New Drug Application. This application, demonstrating both safety and effectiveness of a new drug in both animal and human experiments, must be submitted by a drug company to the FDA before a new drug can be marketed.
neuroleptic  A general term for the antipsychotic drugs (also called major tranquilizers).
neurosis  A type of mental disorder, mostly now referred to as anxiety disorders.
neurotransmitter  A chemical that is released by one neuron and that alters the electrical activity in another neuron.
Nicotiana  Any of several types of tobacco plant, including N. tobacum and N. rustica.
nicotine  The chemical contained in tobacco that is responsible for its psychoactive effects and for tobacco dependence.
nigrostriatal pathway  A group of dopamine-containing neurons that have their cell bodies in the substantia nigra of the midbrain and their terminals in the corpus striatum (basal ganglia), which is part of the extrapyramidal motor system. It is this pathway that deteriorates in Parkinson's disease and on which antipsychotic drugs act to produce side effects resembling Parkinson's disease.
nitrosamines  A group of organic chemicals, many of which are highly carcinogenic. At least four are found only in tobacco, and these might account for much of the cancer-causing property of tobacco.
nonspecific effects  Effects of a drug that are not changed by changing the chemical makeup of the drug. Also referred to as placebo effects.
norepinephrine  A neurotransmitter that might be important for regulating waking and appetite.
NORML  National Organization for the Reform of Marijuana Laws.
NSAIDs  Nonsteroidal anti-inflammatory drugs, such as ibuprofen and naproxen.
nucleus basalis  A group of large cell bodies found just below the basal ganglia and containing acetylcholine. These cells send terminations widely to the cerebral cortex. In Alzheimer's disease, there is a loss of these neurons and a reduction in the amount of acetylcholine in the cortex.
opiate  One of a group of drugs similar to morphine, also referred to as narcotics, and used medically primarily for their analgesic effects. The Greek root for narcotics meant "numbness," and in early pharmacology writings the term was used for many psychoactive drugs that were thought to reduce pain or dull the senses. Also, by extrapolation from the Bureau of Narcotics, the term narcotic came into popular use to refer to any illegal drug (now replaced by the term controlled substance in legal writings).
opiate antagonist  Any of several drugs that are capable of blocking the effects of drugs. Used in emergency medicine to treat overdose and in some addiction treatment programs to block the effect of any illicit opiate that might be taken. Nalorphine and naltrexone are examples.
opium  A sticky substance obtained from the seed pods of the opium poppy and containing the narcotic chemicals morphine and codeine.
organic disorder  For mental disorders, those with a known physical cause (e.g., psychosis caused by long-term alcohol use).
OTC  Over-the-counter. OTC drugs are those drugs that can be purchased without a prescription.
Papaver somniferum  The opium poppy.
paraphernalia  In general, the equipment used in some activity. Drug paraphernalia include such items as syringes, pipes, scales, or mirrors.
parasympathetic  The branch of the autonomic nervous system that has acetylcholine as its neurotransmitter and, for example, slows the heart rate and activates the intestine.