Prescribing in liver disease

Prescribing medications in patients with decompensated liver cirrhosis

Patients with decompensated liver cirrhosis have various serious complications which require multiple drugs for therapeutic or prophylactic use. Majority of the drugs are primarily metabolized and excreted by hepatobiliary system; hence, liver cell necrosis contributes to impaired drug handling in liver failure while portosystemic shunt can alter drug action in cirrhosis. Hence, in order to decide drug dosing in liver failure, 3 important factors need to be considered (1) pharmacokinetic alterations of drugs, (2) pharmacodynamic alteration of drugs, and (3) increased susceptibility of patients to adverse events particularly hepatotoxicity. Though there is no predictable test which can be used to determine drug dosage in patients with decompensated liver cirrhosis, drugs with first pass metabolism require reduction in oral dosages, for high clearance drugs both loading and maintenance dosages need adjustment, for low clearance drugs maintenance dose needs adjustment, whenever possible measuring drug level in the blood and monitoring of adverse events frequently should be done. No evidence-based guidelines exist for the use of medication in patients' with liver cirrhosis. There are hardly any prospective studies on the safety of drugs in cirrhotic patients. According to the experts opinion, most of the drugs can be used safely in patients with cirrhosis, but drug-induced hepatotoxicity may be poorly tolerated by patients with cirrhosis; hence, potential hepatotoxins should be avoided in patients with liver cirrhosis. Potentially hepatotoxic drugs may be used in patients with liver cirrhosis based on the clinical needs and when there are no alternatives available. Caveat for the prescribing medications in patients with cirrhosis the drug dosing should be individualized depending on a number of factors like nutritional status, renal function, adherence, and drug interaction. Monitoring of the liver function at frequent intervals is highly recommended.

Drug use for non-hepatic associated conditions in patients with liver cirrhosis

AIMS

To study the prescribing patterns of practising physicians for the most frequent non-hepatic associated conditions in patients with liver cirrhosis.

METHODS

A multi-centre prospective observational study carried out in 25 Spanish hospitals. Inpatients admitted to gastrointestinal and liver units with a diagnosis of liver cirrhosis were included in five centrally assigned index days, between February and June 1999. Information was collected about pharmacological treatments used on admission and recommended at discharge.

RESULTS

Five hundred and sixty-eight in-patients with a diagnosis of liver cirrhosis (44% alcoholic cirrhosis) and an average number of 2.5 co-morbid conditions were studied: diabetes mellitus (30%), infectious disorders (24%), cardiovascular disease (20%) and active alcoholism (15%)--the most common associated conditions. Chlormethiazole, amoxicillin-clavulanic acid, paracetamol, gliblenclamide, lorazepam, captopril and tiapride were the drugs used most prevalently. The average prescribed daily dose was <1 defined daily dose per day for most medication classes hepatically handled except for calcium channel blockers.

CONCLUSIONS

The present study expands current knowledge of prescribing patterns for associated conditions in patients with underlying liver cirrhosis. Drug dosing was affected in general by the influence of age and hepatic disease on the disposition of drugs, but knowledge on drug selection needs further attention.

Drug-induced liver disease

The incidence of drug-induced liver disease appears to be increasing, reflecting the increasing number of new agents that have been introduced into clinical use over the past several decades. Among the topics covered, the author discusses incidence, diagnosis, risk factors, clinical presentations, hepatitis, and vascular injury. The author also reviews the hepatic injury seen with commonly prescribed drugs, emphasizing newer developments in the field and recent publications and reports.