Prescribing in liver disease

Drugs that undergo extensive 1st pass hepatic metabolism: aspirin, nitrates, levodopa, lidocaine, opiates (especially morphine), propranolol, salbutamol

Ways that liver disease can alter response to drugs:

• impaired drug metabolism
• hypoproteinaemia (so more free drug)
• decreased clotting
• hepatic encephalopathy may be precipitated by some drugs e.g. diuretics, benzodiazepines
• fluid overload (especially with drugs containing sodium)
• hepatotoxic drugs: paracetamol, isoniazid, statins, methotrexate, phenytoin
• many Abx are affected: hepatotoxicity, adverse effects, BM suppression

Effect on pharmacokinetics:

• drug accumulation
• failure to form active/inactive metabolite
• increased bioavailability after oral administration
• alteration…