Intravenous injections of n-propanol (25 mg, 50 mg, 100 mg, 200 mg, 300 mg) provoke blood concentration curves having exponential shapes of dose dependent rate constants after a sufficiently long time (2 min). They have to be seen therefore as a result of a non-linear elimination process controlled by a Michaelis-Menten-kinetic. Using the Lineweaver-Burk-method the characteristic data of metabolism are determined, namely the maximal velocity of metabolizing beta PrOHmax as 2.5 mg/l min and the Michaelis-Menten-constant as 10 mg/l. An increase of the ethanol exposition causes a prolongation of the mean residence time of n-propanol in the body. This phenomenon is to be interpreted as the result of an inhibition of the n-propanol metabolism by ethanol. The inhibition constant KPrOHEtOH concerned with this process is determined experimentally and has a value of 0.1%.