Antipsychotic Medications
Antipsychotics (neuroleptics) are primarily used to treat schizophrenia, bipolar mania, and other psychotic disorders. They work primarily by antagonizing dopamine $D_2$ receptors.
| Generation | Mechanism | Examples |
|---|---|---|
| First-Gen (Typical) | High potency $D_2$ antagonism. | Haloperidol, Chlorpromazine |
| Second-Gen (Atypical) | $D_2$ antagonism + $5-HT_{2A}$ antagonism. | Quetiapine, Risperidone, Olanzapine, Clozapine |
High-Yield Clinical Notes:
- Typical Side Effects: Extrapyramidal symptoms (EPS) such as dystonia, akathisia, and tardive dyskinesia.
- Atypical Side Effects: Higher risk of Metabolic Syndrome (weight gain, dyslipidemia, hyperglycemia). Monitor weight, fasting glucose, and lipids.
- Clozapine: The gold standard for treatment-resistant schizophrenia. Mandatory monitoring for agranulocytosis (CBC checks).
- Neuroleptic Malignant Syndrome (NMS): Life-threatening emergency. Signs: “Lead pipe” rigidity, fever, autonomic instability, and altered mental status. Treat with dantrolene or bromocriptine.