Which class is more likely to cause metabolic side effects such as weight gain and lipid abnormalities?

• A. Typical antipsychotics
• B. SSRIs
• C. Atypical antipsychotics
• D. SNRIs

Answer: (C)

Metabolic side effects like weight gain and lipid abnormalities are most strongly linked to atypical antipsychotics. This class tends to affect multiple metabolic pathways, including signaling through histamine H1 and serotonin 5-HT2C receptors, which can increase appetite and weight. They can also impact insulin sensitivity and lipid metabolism, leading to dyslipidemia and higher risk of metabolic syndrome. Among these drugs, olanzapine and clozapine are well known for causing significant weight gain and lipid changes; other agents in the class such as risperidone and quetiapine also carry notable risk, while ziprasidone and aripiprazole tend to have a more favorable metabolic profile.

In contrast, typical antipsychotics are more associated with movement-related side effects (extrapyramidal symptoms) and have a lower tendency for metabolic disturbances, though some weight gain can occur in some individuals. SSRIs and SNRIs can cause weight changes as well, but they are not as strongly linked to metabolic syndrome as the atypical antipsychotics.

So, the class most likely to cause weight gain and lipid abnormalities is the atypical antipsychotics.