Why Do We Get Side
Effects FromDrugs? Any time you alter you body chemistry you will have some form of side effect. The benefits of the medication will often outweigh the cost of the side effects by improving heath or allowing people to function in daily life. It is up to us to decide.
Blood Brain Barrier (BBB) Endotelialcells
Astrocyte endfeet Trans-cellular passage of drugs Passage of drugs from the bloodstream to the brain is dependent on the ability of the molecules to penetrate through cell membranes.
Targets of psychotropic drugs 30%
of psychotropic drugs target transporter proteins 30% of psychotropic drugs target G protein linked receptors 20% of psychotropic drugs target ligand- gated ion channels 10% of psychotropic drugs target voltage sensitive ion channels 10% of psychotropic drugs target enzymes
Antidepressants Bind to Transporters1. When
Na binds to thetransporter, serotonin alsobinds and renders thetransporter ready.2. When the antidepressantbinds to the transporter itdisplaces serotonin and Na,blocking the transporterStahl SM Stahl’s Essential Psychopharmacology;The Prescriber’s Guide 4th ed 2011
Irreversible Enzyme Inhibitor An irreversible
inhibitor of an enzyme binds to the enzyme in such a way that permanently prevents a substrate from binding. Stahl SM Stahl’s Essential Psychopharmacology; The Prescriber’s Guide 4th ed 2011
Tardive Dyskinesia (TD) Up regulation
of the postsynaptic dopamine receptors. 5% of patients maintained on typical antipsychotics will develop TD in 1 year (25% in 5 years). TD in elderly can be as high 25% in the first year of treatmentKane JM in Bloom FE, Kupfer DJ, Psychopharmacology: The fourth generation ofprogress. Philadelphia Raven 1996National Alliance on Mental illness. Tardive dyskinesia Available atwww.nami.org/ContentGroups/Helpline1/Tardive_Dyskinesia.html