02 - General principles of prescribing in hepatic

General principles of prescribing in hepatic impairment

The Maudsley® Prescribing Guidelines in Psychiatry, Fifteenth Edition. David M. Taylor, Thomas R. E. Barnes and Allan H. Young. © 2025 David M. Taylor. Published 2025 by John Wiley & Sons Ltd. Chapter 8 Hepatic impairment Patients with hepatic impairment may have the following: ■ ■Reduced capacity to metabolise biological waste products, dietary proteins and ­foreign substances such as drugs. Clinical consequences include hepatic encephalopathy and increased dose-­related adverse effects from drugs. ■ ■Reduced ability to synthesise plasma proteins and vitamin K-­dependent clotting ­factors. Clinical consequences include hypoalbuminaemia, leading in extreme cases to ascites. Increased toxicity from highly protein-­bound drugs should be anticipated. There is also an increased risk of bleeding from gastrointestinal irritant drugs and with selective serotonin reuptake inhibitors (SSRIs). ■ ■Reduced hepatic blood flow. Clinical consequences include oesophageal varices and elevated plasma levels of drugs that are subject to first-­pass metabolism. General principles of prescribing in hepatic impairment Liver function tests (LFTs) are a poor marker of hepatic metabolising capacity. Many patients with chronic liver disease are asymptomatic or have fluctuating clinical symptoms. LFTs help evaluate hepatic damage but tell us little about hepatic function. There are few clinical studies relating to the use of psychotropic drugs in people with hepatic disease. The following principles should be adhered to:

1. Prescribe as few drugs as possible.
2. Use lower starting doses, particularly of drugs that are highly protein bound. Tricyclic antidepressants (TCAs), SSRIs (except citalopram), trazodone and Prescribing in hepatic and renal impairment