A client with liver impairment would require the closest monitoring while taking which medication?

The correct answer is Sertraline, which requires closer monitoring in clients with liver impairment due to its hepatic metabolism. When a patient has liver issues, their ability to metabolize medications can be compromised, leading to an increased risk of toxicity and adverse effects. Sertraline, an SSRI, is primarily processed in the liver, and altered liver function may lead to elevated levels of the drug in the bloodstream. This necessitates careful monitoring for potential side effects, which can be more pronounced in individuals with hepatic dysfunction.

While other medications listed, such as Citalopram and Fluoxetine, are also metabolized by the liver, the degree of liver impairment and the specific metabolic pathways may influence the extent of monitoring required. Phenelzine, a monoamine oxidase inhibitor, poses its own risks and management complexities, but in terms of direct hepatic impact and monitoring needs, Sertraline is notably significant due to its metabolic profile. Hence, clients with liver impairment taking Sertraline would require close observation for therapeutic efficacy and safety.