Causation and Drug Effects: Contingencies
(See: Drugs in American Society, 5th, 6th, 7th, 8th, and 9th editions, Erich Goode, McGraw-Hill, 1999/2005/2008/2012/2014. Chapter 2/3)

Do drugs cause things to happen, cause us to behave in certain ways????

Types of Effects:

• These effects are interrelated
• We often categorize and define a drug based upon certain effects and not others (see the DEA's Drugs of Abuse, 2011)
• These effects are related to the contingencies (below) which define the drug experience

Neuro-Pharmacology for Absolute Beginners

• The Brain (Blood-Brain Barrier, image)(blocking nicotine) (cocaine vaccine research: released in Europe, released in USA, "shows promise" 10/09). (Work on a heroin vaccine, 2011-local copy)
• Neurons
• Synapses (gaps between neurons across which neurotransmitters flow)
• Neurotransmitters (table) (keys- if they "fit" into the "locks" (receptors) brain activity is either stimulated or inhibited)
• Receptors (locks- designed to be "attractive" to certain keys).  Some keys fit so perfectly that they don't activate a receptor and they block other keys from gaining access, some keys 'stretch' the receptor and cause the neuron to fire.
• Drugs "work" in many ways.  They may act like indigenous transmitters causing the neuron to "fire," or they may block a receptor site.  Drugs may also provide the "raw material" out of which neurotransmitters are made, or they may affect the availability of other neurotransmitters.

(image courtesy of http://www.lacbc.org/brain.html)

All this is well and good.  However, the potential impact of a specific drug, that is revealed through an analysis such as what we have above, becomes a reality when substances are taken in particular ways by particular people living and interacting in particular places at particular times.  The drug using experience is shaped by a variety of "contingencies."

(credit to Ben Cooper for the table and picture above!)

The Drug Using Experience

Identity

• What is it that people are ingesting?
• Street versus laboratory experimentation
• Bogus or "look-alike" Drugs (see also)
• To adequately discuss the effects of a drug, we must be sure as to what substance we attribute what effects
• DanceSafe. (Other page: https://www.ecstasydata.org/) and LSD Samples Analysis

Purity

• What else is being consumed?
• Quality control
• Identity issue again
• Impact potency of a particular sample, and therefore dose.
• Heroin on the streets (see also, DEA on heroin)(more from 2010)
• Heroin in St. louis 2011

Potency

• How much is needed of a particular drug sample
• The potency of a particular substance can vary: time, manufacturing techniques, form in which it is consumed, etc.
• How much is needed of a particular drug sample

Dose

• Properties of drug are only a potential until a specific dose is ingested
• There are levels at which any drug has no effect
• There are levels at which any drug can produce harm (overdose)
• Cultural and subcultural norms govern how much of a drug is ingested
• Dose-Response Curve. (see image). Specific effects occur at specific levels of ingestion ED versus LD (see chart). Typically a plateau is reached at which additional amounts will no longer produce "more" of a specific effect ("Only go so high") (see also: Wikipedia on the "Plateau Principle").

Drug Fate

• Metabolism
• Half-life
• Toxicity

Drug Mixing

• Synergy
• User experimentation

Route of Administration

Certain drugs, certain ways only. Cultural Norms, Group behaviors, and practicality.

• IV (see image)
• IM
• Subcutaneous (see also)
• Inhalation
• Smoking
• Intranasal
• Mucous absorption
• Transdermal
• Oral

Habituation

• Pharmacological tolerance (associated with physiological dependence)
• Behavioral tolerance (associated with phychological dependence)
• Reverse tolerance (and cannabis)
• Cross tolerance and dependence

Set

• Individual characteristics of the user
• Psychological differences (cannabis and sexual activity)
• Physiological differences

Setting

• Social Context (cannabis and productivity)
• Historical Context
• Legal Context
• Environmental Context
• See: Norman Zinberg's "Drug, Set, and Setting (1984)

Variations in these contingent elements work to produce for particular individuals in particular social contexts the effects that come to be associated with particular substances. We will be studying the variety of substances defined as drugs based on these effects and the classification schemes developed to organize and direct our understanding of drugs.

What is Drug Abuse?

URL: http://www.umsl.edu/~keelr/180/drgeff.html
Owner: Robert O. Keel rok@umsl.edu
References and Credits for this Page of Notes
Last Updated: Tuesday, January 30, 2018 11:57 AM