Paul Walker has topped the Google UK Zeitgeist chart of the most searched for people on the internet in 2013. The late Fast & Furious star, who died in a car crash on 30 November, was laid to rest during a funeral on Sunday.
Understanding First Pass Metabolism. The drug is absorbed from the GI tract and passes via the portal vein into the liver where some drugs are metabolised. Sometimes the result of first pass metabolism means that only a proportion of the drug reaches the circulation. First pass metabolism can occur in the gut and the liver. For example, first pass metabolism occurs in the gut for benzylpenicillin and insulin and in the liver for propranolol, lignocane, chloromethiasole and GTN.
When a drug is administered non-parenterally (orally), a significant portion may be immediately inactivated in either the liver or intestines before it ever reaches the system clrcuJation. Drugs that undergo a significant first pass metabolism will require large oral doses, or will need to be.