[Effect of portasystemic anastomoses in childhood on propranolol pharmacokinetics]

Kinetics of propranolol after oral administration were investigated in 9 children aged 5--11 years with intact liver function who had undergone porto-systemic anastomosis surgery for pylethrombosis and in a 16-year-old boy with a Warren shunt. Bioavailability of the drug had increased by twice the values measured in physiologic liver blood flow; elimination half-life had doubled. These alterations must be taken into consideration in medication, e.g. extreme care must be exercised in the oral administration of "first pass" drugs in porto-systemic shunt patients and it is recommended that the initial dose should be at the level of intravenous administration. The reduced rate of elimination should be taken into account in the case of drugs whose elimination depends on liver blood flow.