Lecture 1: General Drug Info

avatar
Created by
Angela

Cards (20)

  • The brain regions responsible for:

    Vision = occipital
    Judgement = cingulate
    Memory = hippocampus
    Pain = thalamus AND brain stem/spinal cord
    Reward = VTA projects to nucleus accumbens
    Coordination = cerebellum
    Movement = Precentral gyrus / primary motor cortex (located in the frontal lobe)
    Sensation = Somatosensory cortex (located in the parietal lobe)
  • The nervous system communicates faster (faster/slower) and has a smaller (smaller/larger) range of effect than hormones.
  • The two branches of the autonomic nervous system are the PNS and SNS.
  • The peripheral nervous system is divided into the somatic (sensorimotor) and autonomic (PNS, SNS) systems.
  • The SNS is responsible for fright, flight, fight and sex.
  • The PNS is responsible for digestion, energy storage, immune regulation and growth.
  • Sublingual administration is good for high (low/high) lipophilic drugs
  • Rectal route: 50% bypasses the liver. Absorption is irregular (regular/irregular)
  • SC injections act quickly and last a long time
  • Why the BBB makes it hard for things to get in:
    • Brain capillary endothelial cells have continuous tight junctions
  • EPSP = Excitatory Post-Synaptic Potential
    Na+ enters the cell body and carries +ve charge

    IPSP = Inhibitory Post-Synaptic Potential
    Cl- enters the cell body and carries -ve charge

    The only way to get an action potential is to have lots of EPSPs.
    IPSPs inhibit action potentials.
  • Depolarisation involves influx of Na+ while repolarisation involves efflux of K+ via the sodium-potassium pump
  • Competitive antagonism can be reversible or irreversible.
    • reversible = pops on and off receptor
    • irreversible = binds and doesn't come off e.g. poisons
  • Chemical antagonism = Two substances may mix in solution before administration causing activity of drug to be lost
  • Pharmacokinetic antagonism = Once drug has entered the body it’s activity is reduced either by interaction with other medication/ingested compound or being broken down by gut & liver enzymes
    • CYP1A2 oxidises caffeine
    • CYP2C9 oxidises ibuprofen
    • CYP2E1 oxidises alcohol - ALSO needs alcohol dehydrogenase
  • Physiologial antagonism = when the physiological effect of two administered drugs counteract each other e.g. alcohol and methamphetamine
  • Additive: Sum of the effect of each drug to get ‘double’ the effect.
    Synergistic: one drug potentiates the effect of another (more than additive)
  • Refractoriness = lack of response to a drug
  • Tachyphylaxis is used to describe desensitization that occurs very rapidly, sometimes with the initial dose.