Chapter 6

    Cards (9)

    • Psychopharmacology = study of how drugs affect the nervous system and behavior
    • What are psychoactive drugs?

      substances that:
      • alter mood, thought or behavior
      • are used to manage neuropsychological illness
      • are taken recreationally
      • are commonly abu
    • What are the drug administration routes?
      enteral = via digestive system (slow)
      parenteral = not via digestive system (faster)
    • drug asministration route - enteral
      = via the digestive system (slow)
      • oral: through mouth (most convenient)
      • rectal: from the rectum (weak bases)
      • gastric: through stomach (weak acids)
      • buccal/ sublabial: between lip & gum
      • sublingual: under tongue (hydrophilic)
    • Drug administration route - parenteral
      = not via digestive system (faster)
      • subcutaneous: under skin
      • intramuscular: into muscle
      • intravenous: into the atery (hydrophilic)
      • inhalation: into lungs
      • transdermal: through skin (patches)
      • spinal or intracranial: into spinal cord or brain (e.g. epidural, intrathecal) -> no barriers: directly into CSF, so only low dose needed
    • With each obstacle eliminated in route to the brain, a drug's dosage can be reduced by factor of ~10 to induce same effect
      e.g. orally 1000µg =inhaled 100µg = intravenous 10µg
    • Where do drugs end uo in most routes of administration?
      in the blood stream
    • Where do the drugs have to be transferred to be able to act in the brain?
      from blood stream to extracellular fluid
      Note: must overcome blood-brain barrier
    • What is the blood-brain barrier?
      tight junctions between the cells and blood vessels in the brain block passage of most substances
      • only very small uncharched molecules can pass (e.g.O2, CO2)
      • = active transport system (membrane proteins) for amino acids, glucose & fats