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9. Glossary


Excessive use of a substance that can modify psychological or other body function and can lead to effects that are harmful to the individual or to others

Addiction, substance

Compulsive physiological and psychological need for a particular substance


A chemical substance that binds to a receptor and mimics the effect of the physiological (endogenous) substance binding to the receptor


Abnormal fear or anxiety induced by being in crowds or in open spaces—environments which seem difficult to escape from or obtain help


Loss of memory

Amnesia, anterograde

Loss of memory of events subsequent to the action that induced the effect (eg use of a benzodiazepine)


A substance that binds to a receptor but produces no effect and inhibits an agonist from binding to the receptor.

Anticholinergic effects

See Antimuscarinic effects—most anticholinergic effects involve the muscarinic receptor for acetylcholine


A substance that blocks the effects of histamine. Histamine is released when the body mounts an immune response and it is responsible for many allergy-related symptoms

Antimuscarinic effects

Reduction or blocking of the effects of parasympathetic nerves; antimuscarinic effects include dry mouth, difficulty swallowing, blurred vision, confusion, tachycardia, constipation, and urine retention

Apgar score

The result of Apgar test on a newborn 1 minute after birth and again 5 minutes after birth. The test evaluates skin coloration (appearance), heart rate (pulse), reflex irritability (grimace response), activity and muscle tone, and breathing rate and effort (respiration). Each of the five observations is scored on a scale of 0 to 2, with 2 being the best score.


Impaired muscle coordination, thereby affecting the ability to maintain posture or control the strength or direction of limb movement

Avoidant personality

Extreme shyness and sensitivity to rejection, resulting in social withdrawal


Substances derived from barbituric acid which depress the central nervous system and were formerly used mainly as sedatives or hypnotics; barbiturates in current use include phenobarbital and thiopental


Mental functioning involving processes that include perception, recognition, conceptualisation, judgement, and reasoning


The patient and the health professional agreeing on the health outcomes that the patient desires and on the strategy for achieving them


Psychological craving or physiological reliance on a chemical substance; also termed habituation


Loss of sense of personal identity, possibly accompanied by feeling that the individual cannot control own actions or speech


Loss of sense of reality with the individual’s surroundings; the external world seeming unfamiliar and unreal


Loss of inhibition which can lead to lack of restraint and disregard for social conventions


‘Double vision’; a single object seen as two objects


Difficulty with speech caused by impaired control of muscles involved in speech because of disturbed functioning of the nervous system


Feeling uneasy, anxious or dissatisfied


A neurologically based movement disorder involving sustained contraction of the affected muscles, leading to abnormal posturing or repetitive movements or both


Blockage in an artery which obstructs blood flow, usually derived from a blockage elsewhere in the circulation. A common source of pulmonary (lung) embolus is a blood clot (thrombus) in the veins which breaks off and becomes lodged in the pulmonary artery.


A usually inert substance used in the formulation of a medicine

Gamma-aminobutyric acid (GABA)

An amino acid neurotransmitter that reduces nerve cell activity in the brain; it also occurs in the kidney and in the pancreas (islet beta cells)

Glutamic acid

An excitatory amino acid found in abundance in cerebral cortex


Abnormally increased time spent sleeping


A substance that induces sleep


Medicines and Healthcare products Regulatory Agency, the government body responsible for ensuring that medicines and medical devices work and are acceptably safe


Involves or relates to movement of muscle or describes muscle, nerve or brain centre that produces or affects motion


Muscle pain

Myasthenia gravis

A progressive illness with fatigue and muscle weakness, which results from impaired muscle response to nerve impulse (because of autoimmune disorder affecting the neuromuscular junction)


A chemical substance released by a nerve cell at the junction between two nerve cells (synapse), which can stimulate or inhibit the other nerve cell. Examples of neurotransmitters include acetylcholine, dopamine, noradrenaline and serotonin.


Involuntary and jerky eye movement and inability to look steadily at an object


Sensation of numbness or tingling in the skin, popularly known as ‘pins and needles’.


Level of consciousness or cognitive ability linked to motor behaviour


Symptoms involving loss of contact with reality, including hallucinations (affecting hearing, smell, feel or sight), delusions, paranoia, and thought disorders; the individual may appear unusually withdrawn or excited. Psychoses can result from brain injury (eg through trauma, stroke, tumours, and infection), or the use of (usually illicit) drugs, or as a result of psychiatric disorders such as schizophrenia and mania.

Psychotropic action

The ability of a chemical substance to affect brain function, in particular those brain systems which subserve mental activity. The psychotropic action of a drug is usually (but not always) related to an ability to interact with neurotransmitter receptors in the brain.

Pulmonary embolism

Blood clot in the lung


Rapid or excessive breakdown of muscle with urinary excretion of myoglobin


Reduction of anxiety, irritability or excitement; inducing calmness

Sleep hygiene

Conditions that promote sleep: eg fixed times for retiring and waking, avoiding caffeine and alcohol late at night, avoiding heavy meals at night, taking regular exercise (gentle exercise in the evening), and comfortable sleeping environment


A state of mental numbness and near-unconsciousness

Summary of product characteristics (SmPC)

Summary of product characteristics, a document that forms the basis of information for European Union health professionals on how to use a medicinal product safely and effectively; it reflects the data assessed for granting marketing authorisation


Temporary partial or complete loss of consciousness; a faint


Tolerance follows repetitive exposure to a drug, leading to a reduction of the pharmacological effect of that drug


Sensation of whirling or rotation of surroundings and loss of balance