Week 8: Psychopharmacology & Drug Addiction Flashcards
What is psychopharmacology?
study of drug-induced changes in mood, thinking and behaviour
What is a drug?
an exogenous chemical not necessarily for normal cellular functioning which alters the activity of certain cells in the body
Why are psychoactive drugs typically used for?
Alter mood: stimulant, depressant, hallucinogen
Treat psychopathology:
- Anxiolytics -reduce anxious feeling
- Anti-depressants - alleviate negative feelings
- Anti-psychotics - severe forms of psychotic behaviour
When did the modern history of psychopharmacology start?
in the 1950’s with the synthesis of chlorpromazine (an anti-psychotic)
What re the 4 principles of PsychoPharm?
Pharmokinetics
Drug Effectiveness
Effects of repeated administration
Placebo Effects
What is pharmokinetics?
Process in which drugs are absorbed, distributed, metabolised and excreted which is important for effectiveness
What is drug absorption?
mechanisms of drugs getting into the bloodstream
What are routes of administration?
How and how much of the drug gets into the brain, and to be effective drugs must reach site of action within the CNS
Can include: oral, inhalation, nasal, topical etc.
Intravenous is the most effective
What is the Blood Brain Barrier (BBB)?
Barrier for only water soluble molecules, with the BBB protects the passing of chemicals
What is drug effectiveness?
Ability to readily produce certain physiological & behavioural effects - sensitivity and specificity
Best way to measure is the dose response curve
What is the placebo effect?
Important to have as a control in experiments as it may have an effect
It is an inert substance given in lieu of physiologically active drug
What is the difference between agonistic and antagonistic drug action?
Agonistic = promotes NT
Antagonistic = inhibits NT
What are the 4 things that a cell must have to be considered a Neurotransmitter?
- Be synthesised and stored in pre-synaptic neuron
- released in synapse when neuron fire
- cause a post-synaptic effect after it interacts with a receptor
- must be some mechanism for degradation/ reuptake
What is ACh?
Acetylcholine
- Controls HR and has important role in motor movement particularly in the Basal Ganglia
What is the role ACh plays in memory?
Alzheimer’s involves degeneration of ACh neurons in basal forebrain. Drugs that increase ACh are used for treatment
What are the Biogenic Amines (monoamines)?
Norepinephrine (noradrenaline) Epinephrine (adrenaline) Dopamine Histamine Serotonin
with the top 3 being Catecholamines
What is norepinephrine?
originates in pons
form the reticular activating system (excitatory pathway)
Responsible for maintaining cortical arousal
deficiencies are linked to depression and attention deficit disorders
What is dopamine?
Located in the 2 main forebrain pathways Involved in many therapeutic drugs and drugs of abuse Nigrostriatal Pathway: - voluntary movement -deficiencies lead to Parkinson's Ventral Tegmental Area (VTA): - the reward pathway
What is serotonin?
Controls sleep-wake cycle, impulsive behaviour, mood and appetite
Implicated in sleep disorders, anorexia, aggression, depression, obesity
What is the main excitatory and inhibitory NT’s?
Glutamate = excitatory GABA = inhibitory
What is Anxiety?
Feeling of apprehension or fear that lingers Symptoms include: -twitching / trembling - difficulty swallowing - muscle tension -headaches -dry mouth
What are the effects of Benzodiazepines?
Sedation Decreased anxiety anterograde amnesia hypnosis muscle relaxation
