Drugs III

How Do Psychoactive Drugs Enter the Body 


  • Swallowing
  • Snorting
  • Smoking
  • Vaping
  • Inhaling fumes
  • Injection-intramuscular (IM), intravenous (IV), subcutaneous (SC)
  • Topical
  • Sublingual (under the tongue)

Following a Substance Through the Body 


Administration-Substance into person
Absorption-Substance into bloodstream
Distribution-blood carries substance to brain and body tissues
Substance Action-substance interacts with cells
Termination of effect, metabolism, and/or elimination

Time Between Metabolism and Elimination 


  • Half-Life: The amount of time it takes to eliminate half of the original dose of a substance from the body
  • The half-life of a substance affects how long its effects last; then how long it will take to clear the substance from the body


    Factors Influencing the Effects of Drugs 

  • Age
    • Infants and the elderly tend to be the most sensitive to the effects of drugs
  • Gender
    • Women may react more strongly to certain drugs than men
      • They are generally smaller and have a higher proportion of fat than men
  • Body Weight
    • Considerably overweight patient may require an increase in dosage to attain the same therapeutic response as the general population. Conversely, patient who are underweight tend to required lower dosages for the same therapeutic response
  • Dosage
  • Purity and Potency
  • Drug Interactions
    • Other drugs in the person’s blood stream
  • Tolerance
    • regular use versus naive user
  • Set and Setting, environment in which the drug is consumed
    • Wild party versus in a quiet home
  • Time taken to consume drug
    • 10 minutes versus 10 hours
  • Physical size and muscle content
  • Mood or attitude fo the user
    • Angry versus calm, confident versus fearful
  • Expectation of the drug effect
    • Expecting a powerful effect versus expecting a modest drug effect
  • Method of administration
    • The manner in which drugs are taken greatly affects the speed, intensity, and duration of effects

Why do People Use Psychoactive Substances

  • Influences of other people
  • Popular media
  • Escape and self-medication
  • Boredom
  • Rebellion
  • Instant gratification
  • Lack of confidence
  • Misinformation

Risk Factors

Circumstances or events that increase a child’s use of abuse of drugs.  The more likely a child may be to use drugs and develop problems. Risk factors for drug use include:
  • Low grades or failure in school
  • Victim of bullying or cyberbullying
  • Low self esteem
  • Permissive parenting
  • Parent or older sibling drug/alcohol use
  • Living in a community with a high tolerance for smoking, drinking, or drug use among youth
  • Attending a school without strict rules for tobacco, alcohol, or drugs and inconsistent enforcement for breaking those rules
  • Belief that there is little risk in using a drug.