Psychopharmacology: Antipsychotic Medications

Flashcards defining key terminology, pathways, and specific medications related to first, second, and third generation antipsychotics covered in the lecture transcript.

First Generation Antipsychotics (FGAs)

Traditional or typical antipsychotics (such as chlorpromazine and haloperidol) that aggressively block dopamine receptors to treat positive symptoms of schizophrenia, but carry a high risk of extrapyramidal side effects, anticholinergic effects, and elevated prolactin.

Second Generation Antipsychotics (SGAs)

Atypical antipsychotics that block dopamine less tightly via a fast-off mechanism and also block serotonin, resulting in fewer extrapyramidal side effects but a significantly higher risk of weight gain and metabolic syndrome.

Third Generation Antipsychotics (TGAs)

Atypical antipsychotics that act as partial agonists and dopamine stabilizers, balancing dopamine levels where needed with a lower risk of weight gain and extrapyramidal side effects.

Dopamine Hypothesis

The theory that schizophrenia symptoms are related to dopamine activity; excess dopamine in specific brain regions accounts for positive symptoms, though it does not fully explain negative symptoms.

Mesolimbic Pathway

The dopamine highway near the limbic system controlling emotions, pleasure, and reward, where antipsychotic blockade helps alleviate positive symptoms like hallucinations and delusions.

Tuberoinfundibular Pathway

The dopamine pathway close to the hypothalamus and pituitary gland where dopamine normally inhibits prolactin release; blocking dopamine here can trigger elevated prolactin levels.

Gynecomastia

Breast development in males, which can occur as an undesired side effect when dopamine blockade leads to elevated prolactin levels.

Nigrostriatal Pathway

The dopamine pathway responsible for controlling and coordinating motor movements; blocking dopamine in this area causes extrapyramidal side effects.

Extrapyramidal Side Effects (EPSEs)

A group of movement disorders caused by excessive dopamine blockade in the nigrostriatal pathway, including akathisia, bradykinesia, dystonia, tardive dyskinesia, Pisa syndrome, and neuroleptic malignant syndrome.

Mesocortical Pathway

The dopamine pathway that assists with thought organization and evaluating behavior consequences; blocking dopamine here can worsen negative symptoms of schizophrenia.

Chlorpromazine

The first antipsychotic medication ever discovered; a first-generation agent that is highly sedating and aggressively blocks dopamine and acetylcholine receptors.

Haloperidol

A common first-generation antipsychotic that binds tightly to dopamine receptors, effectively treating positive symptoms and acute agitation (often via intramuscular injection) without causing weight gain.

Clozapine

A gold-standard second-generation antipsychotic for positive schizophrenia symptoms that requires strict monitoring due to potentially lethal adverse effects like neutropenia and agranulocytosis.

Agranulocytosis

A severe, potentially lethal drop in white blood cell count (neutropenia) that serves as a critical adverse effect associated with clozapine.

Olanzapine

A second-generation antipsychotic that strongly blocks serotonin, which frequently causes significant weight gain and appetite changes.

Quetiapine

A second-generation antipsychotic that blocks serotonin and acetylcholine, leading to notable side effects of increased hunger, weight gain, and sedation.

Aripiprazole

A third-generation antipsychotic (marketed as Abilify) that functions as a dopamine stabilizer to manage positive and negative symptoms with minimal risk of weight gain or extrapyramidal side effects.

Cariprazine

A third-generation antipsychotic medication (marketed as Vraylar) that acts as a dopamine stabilizer.