Week 4: Licit and Illicit Drug Use: Understanding Addictions
- drug use: taking a drug for the reason it was intended (e.g. for what it was prescribed for)
- drug misuse: the use of a drug for a purpose for which it was not intended
- drug abuse: the excessive use of any drug
1. Describe how set and setting influence the side effects of psychoactive drugs.
- set: the total internal environment or mindset of a person at a time a drug is taken (e.g.
expectations on the effects of the drugs, mood); will affect the experienced side effects
- setting: the drug user’s total external environment; e.g. drug will produce different affect at a
club setting than in at home
2. Outline the list of behaviours generally exhibited by a person with an addiction.
- at least 3 of the following:
- makes excessive use of a substance or behaviour (longer than period of time intended)
- expresses a persistent desire or makes unsuccessful efforts to control use of substance or
- spends great deal of time getting or using substance or engaging in behaviour or recovering
from its effects and after-effects
- frequently too incapacitated by after-effects to fulfill major obligations
- gives up regular activates to use substance or engage in the behaviour
- continues to use substance or participate in the activity despite problems with it
- develops a physical tolerance (needs more to get the same effect)
- exhibits withdrawal when not using the substance or engaging in the behaviour
- uses or engages in behaviour to relieve or avoid withdrawal symptoms 3. Differentiate between physiological and psychological dependence.
- physiological dependence: symptoms that occur in response to the frequent presence of a drug,
esp. tolerance and withdrawal
- psychological dependence: cluster of cognitive, behavioural and physiological symptoms
occurring in one who continues to use a substance despite significant use-related problems
- NOTE: both are so intertwined that the two cannot be separated (i.e. for everyone
psychological state, there is a corresponding physiological one)
4. Name the anatomical regions of the limbic system that play a role in addiction.
- hippocampus, amygdala, nucleus accumbens, ventral tegmental area (VTA), prefrontal cortex
5. Describe the neurochemical effects of heroin on the brain.
- converted by enzymes to morphine once in the brain
- the morphine will bind to opioid receptors which stimulate increase in release of
- dopamine then activates other neurons and user experiences intense rush of pleasure
6. Explain the neurochemical changes that contribute to the development of tolerance.
- some drugs cause over stimulation of the nucleus accumbens through repeated release of
- this causes the nucleus accumbens to decrease the number of dopamine receptors it has (down-
regulation); since there a less dopamine receptors, there requires more dopamine is required to
produce the same effect (need to stimulate more release by more drug!)
- another way that tolerance develops is in altering the cell’s response to the drug
- when drug binds to cell, activates signal pathway, e.g. involving the enzyme adenylyl cyclise,
which causes cell to maintain its activity
- after repeated activation, adenylyl cyclise adapts; need more of the drug to stimulate the cell
7. What does “nurturing through avoidance” mean?
- nurturing through avoidance: repeatedly seeking the illusion of relief to avoid unpleasant
feelings or situations 8. Describe the four common symptoms of addictions.
- compulsion: obsession or excessive preoccupation with the behaviours or drug
- loss of control: the inability to predict reliably whether any isolated occurrence of the
behaviours or use of a drug will be healthy or damaging
- negative consequences: e.g. physical damage, legal trouble, financial problems, academic
failure, relationship difficulties
- denial: the inability to perceive that the behaviours or druge use are self-destructive
9. List the different methods of administering drugs. For which methods are the effects
felt most rapidly?
- oral ingestion: need to pass through digestive system, so relatively slow absorption
- injection: intravenous injection results in extremely effective administration; intramuscular
injection results in much slower (hypodermic needle usually into buttocks or triceps);
subcutaneous injection puts drug into layer of fat directly beneath skin
- inhalation: ingestion of drugs through the nostrils; instantaneous effects but do not last long
(only small amounts can be absorbed and metabolized in the lungs)
- inunction: drugs into body through the skin; patches slowly release chemicals for a consistent
- suppositories: drugs mixed with a waxy medium that are designed to melt at body temperature
(inserted into the anus past the rectal sphincter muscles; wax melts and drug is released and
absorbed through rectal walls into bloodstream)
10. Define the following terms: synergism (a.k.a. potentiation), antagonism, inhibition,
intolerance, and cross-tolerance.
- synergism (potentiation): an interaction of two or more drugs in which the effects of the
individual drugs are multiplied beyond what is normally expected
- antagonism: one drug blocks the action of the other at the receptor site; symptoms are usually
not as serious as synergism - inhibition: effects of one drug are eliminated or reduced by the presence of another drug
- intolerance: when drugs combine in the body resulting in extremely uncomfortable reactions
(e.g. antabuse and alcohol)
- cross-tolerance: person develops a physiological tolerance to one drug and, as a result, a
similar tolerance to other drugs with similar effects
11. What are the risk factors for drug use? When are individuals most vulnerable to
- a “risk-taking” personality; poor economic conditions; dysfunctional family situation;
psychologically distressed; living in a rural area or city; ethnicity; caregiver who abuses drugs;
academic failure; drug-abusing peers; drug availability, or belief that drug use is acceptable
- youth are most venerable during major transitions in their lives, e.g. when a child first enters
school, entering high school, entering college
12. Describe factors that increase the risk of drug dependence.
- physical factors: individual’s genetics and specific neuroanatomy or neurochemistry
- psychological characteristics: experience difficulties controlling impulses, strong need for
excitement and instant gratification, social environment (poverty, peer pressure, parental models)
13. What are the health consequences of addiction? Give examples. Be sure to think
holistically and be specific.
- physical consequences include susceptibility to diseases such as increased risk of cancer,
irritation to respiratory system, suppression of immune system; also blood pressure changes
- psychological consequences include impaired attention, memory
- inability to function in daily living, e.g. reduced motivation for work and study
- impairment can lead to risk to society as well, e.g. impaired driving, criminal activity to support
addiction, jail time, aggressive behaviour
14. What is the most extensively used illicit drug in Canada?
- marijuana! 15. Describe the potential long-term effects of heavy or regular marijuana u