Psychopharmacology PDF

**[Psychopharmacology:]** [Drug-Receptor Interactions:] - Drug action -- interaction between drug and target receptor, which leads to the therapeutic drug "effect" - Many drugs act through competition with naturally produced neurotransmitters - effect magnified If fewer receptors o...

**[Psychopharmacology:]** [Drug-Receptor Interactions:] - Drug action -- interaction between drug and target receptor, which leads to the therapeutic drug "effect" - Many drugs act through competition with naturally produced neurotransmitters - effect magnified If fewer receptors or less competing neurotransmitter [Target in Pharmacotherapy:] - Dopamine: e.g., D2 antagonist used as antipsychotics and mood stabilisers - Serotonin: SERT inhibitors used as antidepressants and treat anxiety disorders - Glutamate: e.g., glutamate modulators used as mood stabilisers - GABA-A agonists used as sedatives [Choice of Antipsychotic:] - Typical vs Non-Typical - Side-effects vs Therapeutic effects - Second Generation Antipsychotic first line - Clozapine efficacy after treatment trials with two antipsychotics [Therapeutic Window of drug occupancy at dopamine:] - For FGA, Occupying \> 60% striatal D2 receptors reduces psychotic symptoms - Beyond 80% impacts on motor function, leads to parkinsonism - Threshold for response differs across SGA, but threshold for EPS remains at 80% regardless of drug [Side-effects and complications:] - Parkinsonism, hyperprolactinaemia, metabolic - Late: Tardive Dyskinesia - Emergency: Neuroleptic malignant syndrome [Antidepressant Pharmacotherapy: ] First Line -- SSRIs - Occupies subcortical serotonin transporter - Decreases activity in locus coeruleus - Increases connectivity between anterior cingulate cortex and limbic regions - Examples include sertraline, fluoxetine, citalopram - Relatively safe in overdose - Side effects: GI, sexual symptoms, hyponatraemia - Withdrawal effects [Other agents in depression:] - SNRIs (e.g., Venlafaxine) - Noradrenaline & Serotonin Antagonist - Lithium - MAOIs - ECT [ECT: ] - Origins in mistaken idea that schizophrenia and epilepsy were mutually exclusive - Controversial treatment based on media portrayal and historical use - Stimulates neurogenesis in preclinical models - Side-effects: headache, nausea, confusion, amnesia [Prophylaxis:] Lithium First Line: - Reduced risk of relapse - Reduced risk of suicide - Useful for treatment resistant depression - Needs regular blood tests to check levels, kidney function and thyroid function