Which medication is contraindicated in patients with liver disease?

The correct choice is disulfiram, as it is contraindicated in patients with liver disease due to its metabolism primarily being hepatic. Disulfiram functions as a deterrent for alcohol consumption by inhibiting the enzyme acetaldehyde dehydrogenase, leading to an unpleasant reaction when alcohol is ingested. Since individuals with liver disease often have compromised liver function, administering disulfiram can result in elevated levels of the drug in the body and increase the risk of hepatotoxicity or other severe side effects.

Other medications listed, such as methadone, buprenorphine, and naltrexone, may require caution in use with liver impairment but are not strictly contraindicated. Methadone can be adjusted for those with liver dysfunction, buprenorphine has a dependency on liver metabolism but can be prescribed with monitoring, and naltrexone can be used with caution in cases of mild liver impairment. However, disulfiram remains the primary concern in this context because of the severe risks associated with liver damage.