Psychopharmacology Flashcards
Is acetylcholine excitatory or inhibitory?
Excitatory
Is glutamate excitatory or inhibitory?
Excitatory
Is dopamine excitatory or inhibitory?
Excitatory
Is GABA excitatory or inhibitory?
Inhibitory
Is serotonin excitatory or inhibitory?
Inhibitory
Is noradrenaline excitatory or inhibitory?
Both, depending on the receptor
What is the mechanism of action for SSRIs?
Bind to the SERT (serotonin transporter) on the presynaptic neuron to inhibit the reuptake of serotonin, and increase the amount of serotonin in the synaptic cleft. This increases stimulation of post-synaptic neurons
What are the side effects of SSRIs?
Feeling agitated, shaky or anxious, feeling or being sick.
indigestion, diarrhoea or constipation, sexual dysfunction (loss of libido, difficulty getting and maintaining an erection, difficulty orgasming)
What are some examples of SSRIs?
Fluoxetine, paroxetine, citalopram, sertraline
What is the mechanism of action of SNRIs?
Bind to the SERT and NAT (noradrenaline transporter) on the presynaptic membrane to inhibit their uptake, and increase the amount of neurotransmitter in the synaptic cleft
What are the side effects of SNRIs?
Feeling agitated, shaky or anxious.
feeling or being sick.
indigestion, diarrhoea or constipation
What are some examples of SNRIs?
Venlafaxine, duloxetine
What are the side effects of TCA antidepressants?
Blocks muscarinic receptors too - dry mouth,
slight blurring of vision, constipation, problems passing urine, drowsiness, dizziness, weight gain
What is the mechanism of action of TCA anti-depressants?
Bind to the SERT and NAT (noradrenaline transporter) on the presynaptic membrane to inhibit their uptake, and increase the amount of neurotransmitter in the synaptic cleft
What are some examples of TCA antidepressants?
Lofepramine, amitriptyline
What is the mechanism of action of monoamine oxidase inhibitor anti-depressants?
Inhibit the action of mono-amine oxidase enzymes (MAO-A and MAO-B), to reduce the breakdown of mono-amine neurotransmitters and increase their availability for post synaptic transmission
MOA-A breaks down serotonin, dopamine, melatonin, adrenaline and noradrenaline, so these are increased
Remeber - similar to PD, these drugs inhibit the breakdown of dopamine
What are some examples of MAOI anti-depressants?
Phenelzine
What is the mechanism of action of NaSSA antidepressants? (noradrenergic and specific serotonergic)
Antagonises the adrenergic alpha2-autoreceptors in the presynaptic neuron membrane – these receptors inhibit exocytosis of adrenaline or noradrenaline, so antagonising them increases exocytosis of the NTs.
What are some examples of NaSSA antidepressants?
Mirtazapine
What is the mechanism of action for serotonin antagonists and reuptake inhibitors (SARIs)
Inhibits the reuptake of serotonin by blocking the serotonin transport protein, antagonises 5-HT-2A receptors, H1 receptors, and alpha-1-adrenergic receptors, and redirects the serotonin to areas that help regulate mood
I think 5HT2a has a wider role in things outside of mood stabilisation, so by blocking it you redirect more to mood?
What is an example of a SARI antidepressant?
Trazodone
What is the mechanism of action of anti-convulsants for anxiety?
Inhibits release of excess excitatory neurotransmitters like glutamate by binding to the widely distributed voltage-dependent sodium/calcium channels in the overexcited neurons of the brain and spinal cord
What are the side effects of carbamazepine?
Carbamazepine - CARBA MEAN - confusion, ataxia, blurred vision, aplastic anaemia, bone marrow suppression, eosinophilia, agranulocytosis, neutropenia. Also an enzyme inducer.
What is an example of an anti-convulsant used for anxiety?
Pregabalin
What is the mechanism of action of benzodiazepines used for anxiety?
Benzos enhance the activity of the inhibitory neurotransmitter GABA by facilitating it’s binding to GABA receptors, producing a sedative effect
What are the side effects of benzodiazepines for anxiety?
Drowsiness, difficulty, concentrating, headaches, vertigo, an uncontrollable shake or tremble in part of the body (tremor) , low sex drive
What are some examples of benzodiazepines used for anxiety?
Usually diazepam
What is the function of the mesolimbic dopaminergic pathway and where does it travel from and to?
Reward pathway, transmitting dopmaine from the ventral tegmental area to the ventral striatum
What is the function of the mesocortical dopaminergic pathway and where does it travel from and to?
Cognition and emotion, transmitting dopamine from the VTA to the prefrontal cortex
What is the function of the nigrostriatal dopaminergic pathway and where does it travel from and to?
Movement regulation, transmitting from the substantia nigra in the midbrain to the caudate nucleus and putamen in the dorsal striatum
What is the function of the tuberoinfundibular dopaminergic pathway and where does it travel from and to?
Regulates secretion of pituitary hormones, transmitting from the infundibular nucleus of the hypothalamus
What causes positive symptoms in schizophrenia?
Hyperactivity of dopamine D2 receptorsin the mesolimbic pathway
What causes negative symptoms in schizophrenia?
Negative symptoms, such as flattened affect, are attributed to thehypoactivity of the dopamine D2 receptorsin the mesocortical pathway
What are the extrapyramidal side effects of antipsychotics and which type are they most common with
Acute Dystonia
Akathisia
Parkinsonism
Tardive dyskinesia
(ADAPT)
What are the common signs of neuroleptic malignant syndrome?
Triad of fever, muscle rigidity and altered mental status (drowsiness, agitation, confusion, delirium, coma), as well as autonomic dysfunction (labile BP, tachypnoea, tachycardia, sweating and flushing)
What are the signs of anticholinergic toxicity?
Flushing and feeling hot (from vasodilation), anhidrosis (dry mucous membranes, not sweating), mydriasis, fever, urinary retention, tachycardia, arrhythmias
Progresses to altered mental status (delirium, hallucinations, agitation, restlessness, confusion),
ACh controls the parasympathetic NS, gland secretion (tears, saliva, digestive juices, milk), urine release, cognitive functions such as memory etc
What is the mechanism of action of first generation antipsychotics?
Inhibition of D2 dopaminergic receptors in the mesolimbic pathway of the brain, leading to a decrease in the incidence of positive symptoms. They also have noradrenergic, cholinergic and histaminergic blocking properties.
What are some examples of common anticholinergic side effects of typical antipsychotics?
Dry skin, blurred vision, tachycardia, constipation, vomiting, sedation (due to antihistamine effects),
What are some examples of first generation antipsychotics?
Haloperidol, droperidol, fluphenazine, chlorpromazine, prochlorperazine, loxopine
What is the mechanism of action of second generation antipsychotics?
Inhibition of D2 dopamine receptors in the mesolimbic pathway of the brain, leading to a decrease in the incidence of positive and negative symptoms. This is as well as serotonin receptor (5-HT2A) antagonist action
Is QTc prolongation more of a concern with first or second generation antipsychotics?
Second generation
Are extrapyramidal side effects more common in first or second generation antipsychotics?
First generation
What are some common or dangerous side effects of clozapine?
Common: hypersalivation, tachycardia, hypotension, constipation
Serious: agranulocytosis and leukopenia, bowel ileus/obstruction, lower seizure threshold, myocarditis/cariomyopathy
What are some examples of second generation antipsychotics?
Olanzapine, quetiapine, clozapine, risperidone, Iloperidone, aripiprazole
What are the signs of lithium toxicity?
- Nausea, vomiting, tremor, fatigue (mild)
- Confusion, agitation, delirium, tachycardia, hypertension (moderate)
- Coma, seizures, hyperthermia, hypotension (severe)
What are the theorised mechanisms of action of lithium?
It’s not well understood, but it’s thought that it either interferes with inositol triphosphate formation or cAMP formation
What are the types of lithium?
Lithium carbonate, lithium citrate
What anticonvulsants are used as mood stabilisers?
Carbamazepine, lamotrigine, valproate
What antipsychotics are used as mood stabilisers in an acute manic episode?
Haloperidol, olanzapine, quetiapine, risperidone
For how long should antidepressants be continued before stopping, to reduce the risk of relapse?
Antidepressants should be continued for at least 6 months after remission of symptoms to decrease risk of relapse