Metabolic syndrome is most commonly associated with which class of antipsychotics?

Explanation

## Metabolic Syndrome and Antipsychotics **Key Point:** Atypical antipsychotics, particularly those with potent 5-HT2C receptor antagonism (clozapine, olanzapine), carry the HIGHEST risk of metabolic syndrome, including weight gain, dyslipidemia, hyperglycemia, and insulin resistance. ### Mechanism of Metabolic Dysfunction 1. **5-HT2C Antagonism** — blocks satiety signals in the hypothalamus → increased appetite and weight gain 2. **H1 Receptor Antagonism** — sedation and metabolic slowdown 3. **Muscarinic M3 Antagonism** — impaired glucose homeostasis 4. **Direct insulin secretion impairment** — independent of weight gain ### Risk Hierarchy by Agent | Antipsychotic | Metabolic Risk | Weight Gain | Glucose Risk | Lipid Risk | |---|---|---|---|---| | **Clozapine** | **Very High** | **Severe** | **High** | **High** | | **Olanzapine** | **Very High** | **Severe** | **High** | **High** | | Risperidone | Moderate-High | Moderate | Moderate | Moderate | | Quetiapine | Moderate-High | Moderate | Moderate | Moderate | | Aripiprazole | Low | Minimal | Minimal | Minimal | | Haloperidol | Very Low | Minimal | Minimal | Minimal | | Chlorpromazine | Low-Moderate | Mild-Moderate | Low | Low | **High-Yield:** Olanzapine and clozapine carry the highest metabolic burden among ALL antipsychotics. Aripiprazole (partial D2 agonist) and high-potency typicals (haloperidol) have minimal metabolic risk. **Clinical Pearl:** Metabolic monitoring (fasting glucose, lipid panel, weight, waist circumference) is MANDATORY within 3 months of initiating atypical antipsychotics, especially clozapine and olanzapine. **Mnemonic:** **CLOZ-OLANZ = METABOLIC DANGER** — Clozapine and Olanzapine carry the highest risk; remember 5-HT2C blockade = appetite dysregulation.