How long before an average cup of coffee enters your system..what would the caffeines peak time and half life be?

? cup of coffee but: For coffee, peak time ; 1/2 life depend upon amount ; binding capacity of active metabolites which vary with brands. For otc caffeine pills the half life assuming normal liver and kidney functioning is 3-7/hrs. The metabolism is thru the livers cyp450 enzyme system: 1a2 substrate. Information obtained from epocrates online.

By average 5 hr half: By average the half life of caffeine itself is 5 hours. It peaks 0.5-2 hours. And it will take 3-4 half lives before it clears out of your body assuming this is a young healthy adult.