Drug, not metabolized by liver is : (DNB Nov 2009)
a. Penicillin G is metabolized mainly in kidney. Pharmacokinetics of PnG is dominated by very rapid renal excretion (10%), by glomerular filtration and rest by tubular secretion (90%).
b. Rest of the drugs given in the question erythromycin cimetidine and phenytoin are metabolized in the liver.