Which drug can increase serum bilirubin by inducing cholestasis?

Chlorpromazine is known to increase serum bilirubin levels by inducing cholestasis. Cholestasis refers to the impairment of bile flow, which can lead to the accumulation of bile acids and bilirubin in the bloodstream. Chlorpromazine, an antipsychotic medication, can cause cholestatic liver injury as a side effect, which ultimately results in elevated levels of bilirubin.

The other drugs listed do not typically induce cholestasis in the same manner. For example, phenobarbital is generally known to enhance bile flow and does not commonly lead to cholestatic liver injury or increased bilirubin. Acetaminophen primarily affects liver function through a different mechanism, often causing hepatotoxicity rather than cholestasis. Similarly, ibuprofen is a nonsteroidal anti-inflammatory drug (NSAID) that is not associated with cholestasis or significant effects on bilirubin levels under normal circumstances. Thus, chlorpromazine stands out as the drug recognized for its capacity to induce cholestasis and increase serum bilirubin.