Drug Recognition Expert (DRE) Exam Glossary &
Definitions 2025/2026 – Complete Study Guide for
Law Enforcement & Certification Exams/Drug
Recognition Expert.
Accommodation Reflex
The adjustment of the eyes for viewing at various distances. Meaning the pupils will
automatically constrict as objects move closer and dilate as objects move further away.
Addiction
Habitual, psychological, and physiological dependence on a substance beyond one's voluntary
control.
Additive Effect
One mechanism of poly drug interaction. For a particular indicator of impairment, two drugs
produce an additive effect if they both affect the indicator in the same way. (Cocaine-elevates
PR + PCP-elevates PR= produces additive effect on the PR)
Afferent Nerves/Sensory Nerves
"Sensory Nerves" Nerves that carry messages to the brain, from various parts of the body,
including sense organs. (Afferent- "A **** thats hot")
Alkaloid
Chemical that is found in, and can be physically extracted from, some substance. EX: morphine
is a natural alkaloid of Opium. It does not require a chemical reaction to produce morphine
form opium.
Analog (of a drug)
Analog of a drug is a chemical that is very similar to the drug, both in terms of molecular
structure and in terms of psychoactive effects. EX: Ketamine is an analog of PCP.
Analgesic
A drug that relieves or allays pain.
Anesthetic
,A drug that produces a general or local insensibility to pain and other sensation.
Arrhythmia
An abnormal heart rhythm.
Artery
The strong, elastic blood vessels that carry blood away from the heart.
Autonomic Nerve
A motor nerve that carries messages to the muscles and organs that we do not consciously
control. There are two types of autonomic nerves: sympathetic & parasympathetic.
Axon
The part of a neuron (nerve cell) that sends out a neurotransmitter.
BAC
(Blood Alcohol Concentration)- the percentage of alcohol in a person's blood.
BrAC
(Breath Alcohol Concentration)- the percentage of alcohol in a person's blood as measured by a
breath testing device.
Blood Pressure
The force exerted by blood on the walls of the arteries. Blood pressure changes continuously, as
the heart cycles between contraction and expansion.
Bradycardia
Abnormally slow heart rate.
Bradypnea
Abnormally slow rate of breathing.
Bruxism
Grinding the teeth. (Behavior often seen in a person who is under the influence of
cocaine/other CNS stimulant)
Cannabis
Drug category that includes marijuana, hashish, and marinol. Active ingredient in marijuana and
hashish is a chemical called delta-9 tetrahydocannabinol (THC).
,Carboxy THC
A metabolite of THC (tetrahydrocannabinol).
Cheyne-Stokes Respiration
Abnormal pattern of breathing. Marked by breathlessness and deep, fast breathing.
CNS (Central Nervous System)
A system within the body consisting of the brain, the brain stem, and spinal cord.
CNS Depressants
One of the seven drug categories that include: combinations, anti-depressants, barbiturates,
anti-anxiety tranquilizers, non-barbiturates, anti-psychotic.
What does CABANA stand for and what drug category is it associated with?
C-combinations, A-anti-depressants, B-barbiturates, A-anti-anxiety tranquilizers, N-non-
barbiturates, A-anti-psychotic. It is associated with the CNS Depressants category.
CNS Stimulants
One of the seven drug categories. CNS stimulants include: Cocaine, amphetamines, and others.
Conjuctivitus
An inflammation of the mucous membrane that lines the inner surface of the eyelids caused by
infection, allergy, or outside factors. Commonly known as "pink eye".
Convergence
The "crossing" of the eyes that occurs when a person is able to focus on a stimulus as it is
pushed slowly toward the bridge of their nose. (See also "Lack of convergence")
Crack/ Rock
Cocaine base, appears as a hard chunk from resembling pebbles or small rocks. It produces a
very, intense but relatively short duration "high."
Cirriculum Vitae
A written summary of a person's education, training, experience, noteworthy achievements and
other relevant information about a particular topic.
Cyclic Behavior
, A manifestation of impairment due to certain drugs, in which the suspect alternates between
periods (or cycles) of intense agitation and relative calm. EX: sometimes observed in subjects on
PCP.
Delerium
A brief state characterized by incoherent excitement, confused speech, restlessness, and
possible hallucinations.
Dendrite
The part of a neuron (nerve cell) that receives a neurotransmitter.
Diacetyl Morphine
The chemical name for Heroin.
Diastolic
The lowest value of blood pressure. The blood pressure reaches its diastolic value when the
heart is fully expanded, or relaxed (diastole).
Diplopia
Double vision.
Dissociative Anesthetics
One of the seven drug categories that include drugs that inhibits pain by cutting off or
disassociating the brain's perception of pain.
Divided Attention
Concentrating on more than one thing at a time. The four psychophysical test used by DREs
require the subject to divide their attention.
What are the divided attention psychophysical test a DRE conducts?
Modified Romberg, Walk & Turn, One Leg Stand, & Finger to Nose.
Downside Effect
An effect that may occur when the body reacts to the presence of a drug by producing
hormones or neurotransmitters to counteract the effects of the drug consumed.
Drug
Any substance that, when taken into the human body, can impair the ability of the person to
operate a vehicle safely.
Definitions 2025/2026 – Complete Study Guide for
Law Enforcement & Certification Exams/Drug
Recognition Expert.
Accommodation Reflex
The adjustment of the eyes for viewing at various distances. Meaning the pupils will
automatically constrict as objects move closer and dilate as objects move further away.
Addiction
Habitual, psychological, and physiological dependence on a substance beyond one's voluntary
control.
Additive Effect
One mechanism of poly drug interaction. For a particular indicator of impairment, two drugs
produce an additive effect if they both affect the indicator in the same way. (Cocaine-elevates
PR + PCP-elevates PR= produces additive effect on the PR)
Afferent Nerves/Sensory Nerves
"Sensory Nerves" Nerves that carry messages to the brain, from various parts of the body,
including sense organs. (Afferent- "A **** thats hot")
Alkaloid
Chemical that is found in, and can be physically extracted from, some substance. EX: morphine
is a natural alkaloid of Opium. It does not require a chemical reaction to produce morphine
form opium.
Analog (of a drug)
Analog of a drug is a chemical that is very similar to the drug, both in terms of molecular
structure and in terms of psychoactive effects. EX: Ketamine is an analog of PCP.
Analgesic
A drug that relieves or allays pain.
Anesthetic
,A drug that produces a general or local insensibility to pain and other sensation.
Arrhythmia
An abnormal heart rhythm.
Artery
The strong, elastic blood vessels that carry blood away from the heart.
Autonomic Nerve
A motor nerve that carries messages to the muscles and organs that we do not consciously
control. There are two types of autonomic nerves: sympathetic & parasympathetic.
Axon
The part of a neuron (nerve cell) that sends out a neurotransmitter.
BAC
(Blood Alcohol Concentration)- the percentage of alcohol in a person's blood.
BrAC
(Breath Alcohol Concentration)- the percentage of alcohol in a person's blood as measured by a
breath testing device.
Blood Pressure
The force exerted by blood on the walls of the arteries. Blood pressure changes continuously, as
the heart cycles between contraction and expansion.
Bradycardia
Abnormally slow heart rate.
Bradypnea
Abnormally slow rate of breathing.
Bruxism
Grinding the teeth. (Behavior often seen in a person who is under the influence of
cocaine/other CNS stimulant)
Cannabis
Drug category that includes marijuana, hashish, and marinol. Active ingredient in marijuana and
hashish is a chemical called delta-9 tetrahydocannabinol (THC).
,Carboxy THC
A metabolite of THC (tetrahydrocannabinol).
Cheyne-Stokes Respiration
Abnormal pattern of breathing. Marked by breathlessness and deep, fast breathing.
CNS (Central Nervous System)
A system within the body consisting of the brain, the brain stem, and spinal cord.
CNS Depressants
One of the seven drug categories that include: combinations, anti-depressants, barbiturates,
anti-anxiety tranquilizers, non-barbiturates, anti-psychotic.
What does CABANA stand for and what drug category is it associated with?
C-combinations, A-anti-depressants, B-barbiturates, A-anti-anxiety tranquilizers, N-non-
barbiturates, A-anti-psychotic. It is associated with the CNS Depressants category.
CNS Stimulants
One of the seven drug categories. CNS stimulants include: Cocaine, amphetamines, and others.
Conjuctivitus
An inflammation of the mucous membrane that lines the inner surface of the eyelids caused by
infection, allergy, or outside factors. Commonly known as "pink eye".
Convergence
The "crossing" of the eyes that occurs when a person is able to focus on a stimulus as it is
pushed slowly toward the bridge of their nose. (See also "Lack of convergence")
Crack/ Rock
Cocaine base, appears as a hard chunk from resembling pebbles or small rocks. It produces a
very, intense but relatively short duration "high."
Cirriculum Vitae
A written summary of a person's education, training, experience, noteworthy achievements and
other relevant information about a particular topic.
Cyclic Behavior
, A manifestation of impairment due to certain drugs, in which the suspect alternates between
periods (or cycles) of intense agitation and relative calm. EX: sometimes observed in subjects on
PCP.
Delerium
A brief state characterized by incoherent excitement, confused speech, restlessness, and
possible hallucinations.
Dendrite
The part of a neuron (nerve cell) that receives a neurotransmitter.
Diacetyl Morphine
The chemical name for Heroin.
Diastolic
The lowest value of blood pressure. The blood pressure reaches its diastolic value when the
heart is fully expanded, or relaxed (diastole).
Diplopia
Double vision.
Dissociative Anesthetics
One of the seven drug categories that include drugs that inhibits pain by cutting off or
disassociating the brain's perception of pain.
Divided Attention
Concentrating on more than one thing at a time. The four psychophysical test used by DREs
require the subject to divide their attention.
What are the divided attention psychophysical test a DRE conducts?
Modified Romberg, Walk & Turn, One Leg Stand, & Finger to Nose.
Downside Effect
An effect that may occur when the body reacts to the presence of a drug by producing
hormones or neurotransmitters to counteract the effects of the drug consumed.
Drug
Any substance that, when taken into the human body, can impair the ability of the person to
operate a vehicle safely.
