MT6314 ANTIPSYCHOTICS AND ANTIDEPRESSANTS Flashcards
Study of the drugs that affect cognition, affect, and behavior of an individual
Psychopharmacology
Psychopharmacology includes the study of what drugs?
Antidepressants
Antipsychotics
Classic Mood Stabilizers
Stimulants
Benzodiazepines
What is psychosis?
Inability to distinguish between what is real and what is not real
Psychosis involves?
̶ Delusions
̶ Hallucinations
̶ Disorganized thinking with clear sensorium
What is the most common psychotic disorder?
Schizophrenia
Schizophrenia is characterized by?
̶ Structural and functional changes in the brain
̶ Dysregulated neurotransmitters
Neuronal Networks of Psychosis
Dopamine theory
NMDA theory
Serotonin theory
NMDA theory effect on NMDA receptors?
- NMDA receptor hypofunction
What neuronal pathway is the main reason behind Schizophrenia?
Dopamine pathway
Serotonin theory is defined as?
- 5-HT2A receptor hyperfunction in the cortex
Purpose of Antipsychotic drugs?
- Improve mood and reduce anxiety
Type of antipsychotic drug with high incidence of EPS
Neuroleptic
Classical drugs affinity?
D2»_space; 5-HT2 receptors
Atypical / Newer agents affinity?
5-HT2»_space; D2 receptors
Classes of older antipsychotics?
Phenothiazine
Thioxanthine
Butyrophenone
Antipsychotics are well absorbed when administered ______
Orally
Antipsychotics are lipid or water soluble?
Lipid
Antipsychotics are extensively bound to?
Plasma proteins
Antipsychotics have long or short half lives?
Long
Parenteral forms of antipsychotics?
- Fluphenazine
- Haloperidol
- Ziprasidone
- Olanzapine
- Aripiprazole
Schizophrenia is due to excess of what in where?
functional DA in mesocortical tracts in the brain
Types of Dopamine receptors
̶ GPCR, D1-D5
Location of D2 receptors?
in the caudate, putamen, cortex, hypothalamus – negatively coupled to adenylyl cyclase
Blockade of D2 receptors leads to?
EPS (tremor, slurred speech, akathisia, dystonia)
Has affinity for other receptors and less EPS
- Atypical antipsychotics
All antipsychotic drugs block H1 receptor to some degree except?
̶ Haloperidol
̶ Iloperidone
̶ Lurasidone
Antagonist for D2 blockade?
Clozapine
Weak agonist for D2 blockade?
Olanzapine (+)
Quetiapine (+)
Aripiprazole (+)
Brexipiprazole (+)
Agonist for D4 blockade?
Haloperidol (+)
Iloperidone (+)
Asenapine (++)
Clozapine (++)
Aripriprazole (+)
Brexipriprazole (+)
Antagonist for alpha1 blockade?
Lurasidone
Cariprazine
Antagonists for 5-HT2 blockade?
Haloperidol
Molindone
Agonists for M blockade?
Most phenothiazines and thioxanthenes (+)
Thioridazine (+++)
Molindone (+)
Paliperidone (+)
Clozapine (++)
Olanzapine (++)
Quetiapine (+)
Antagonists for H1 blockade?
Haloperidol
Iloperidole
Lurasidone
Effect is dopamine receptor blockade
First generation drugs
Underlies antipsychotic effect
Mesocortical-mesolimbic path
Antiemetic effect in the Mesocortical-mesolimbic path due to?
blockade of the chemoreceptor trigger zone
Common adverse effects in first generation antipsychotics?
̶ Extrapyramidal symptoms, hyperprolactinemia (1st Generation)
Clinical use of antipsychotics?
- Treatment of schizophrenia
- Mania
- Tourette syndrome
- Alzheimers and Parkinsonism
How long do effects of antipsychotics take for treating Schizophrenia?
Effects take several weeks to develop
lower cost, EPS
1st gen
improves negative symptoms (emotional blunting,
social withdrawal, lack of motivation)
2nd gen
For treating mania, antipsychotics should be given with?
lithium
For treating mania, 2nd generation antipsychotics should be given with?
benzodiazepines
Drugs for prevention of manic phase of bipolar disorder
o Aripiprazole, olanzapine, asenapine
Drugs for prevention of bioplar depression
o Quetiapine, lurasidone, olanzapine, carizapine
Drugs for Tourettes syndrome
Molindone
What develops Parkinson-like symptoms?
Dose-dependent EPS
Dose-dependent EPS is common with?
Common with Haloperidol and more potent piperazine derivatives (Fluphenazine, trifluoperazine)
Dose-dependent EPS is infrequent with?
2nd generation drugs, Clozapine
Methods to deal with dose-dependent EPS?
Mx: reduce dose, use of antimuscarinic agents
Other neurologic dysfunction in the toxicity of antipsychotics are seen in?
akathisia, dystonias
Instances of akathisia, dystonias respond to?
Also respond to antimuscarinic agents, or diphenhydramine
Why do the autonomic effects of toxicity occur?
̶ Due to blockade of peripheral muscarinic and alpha receptors
Order of strength of autonomic effects?
Thioridazine»clozapine and atypicals»haloperidol
Atropine like effects are ? and treated by?
Dry mouth, constipation, urinary retention – Thioridazine and Chlorpormazine
Caused by alpha blockade
Postural Hypotension
Choreoathetoid movements of the lip and buccal muscle
Tardive dyskinesia
Is tardive dyskinesia reversible?
May be irreversible
What increases severity of the symptoms in tardive dyskinesia?
Antimuscarinic drugs that improve EPS
T or F: Switching to Clozapine for treating tardive dyskinesia improves the condition
F, does not exacerbate only
How to temporarily improve the condition of tardive dyskinesia?
increasing neuroleptic dosage
Endocrine effects in antipsychotic toxicity?
Hyperprolactinemia, gynecomastia, infertility due to D2 blockade in pituitary, prominent with Risperidone
Who are prone to NMS?
Patients sensitive to the EPS
How to treat NMS?
̶ Treat with dantrolene, diazepam, dopamine agonists
Sedation in antipsychotic toxicity is marked in what drug?
Chlorpromazine
Least sedating antipsychotics?
fluphenazine and haloperidol; aripiprazole and lurasidone
Visual toxicities for antipsychotics?
̶ Visual: retinal deposits with thioridazine
Cardiac effects of antipsychotic toxicity?
̶ Cardiac rhythm abnormalities: thioridazine, quetiapine, ziprasidone
What causes agranulocytosis and seizure a high doses?
Clozapine
Commonly used for manic phase of bipolar disorder
Lithium
Why is important to monitor levels of lithium in the plasma?
to establish effective and safe dosage
MOA of lithium?
- inhibits enzymes for recycling neuronal membrane phosphoinositides
- depletion of PIP2 , IP3, DAGs
- prevents amine neurotransmission
Antiseizure drugs include?
̶ Valproic acid
̶ Carbamazepine and lamotrigine