Pot basics
Doing drugs of any kind, even the nicer natural ones, makes it even more imperative to flush and to take liver-supporting herbs and vits. :)
Marijuana IS broken down in the liver, which then sends the catabolic remains to the kidneys to be flushed out, which is why a urine test can discover pot use. They look for the chemicals that the liver creates to break it down. So it's a good idea to drink lots of water to help the kidneys.
Pot keeps the liver really busy if you smoke a lot. If the liver gets behind, the THC and DBC (I think that's the intials for THC that breaks down thanks to oxygen and bad storage processes) gets stored in other major organs, especially the fatty tissue surrounding them. So if you don't keep your liver clean, you could be compromising other organs, such as the gonads, testes, ovaries. For some reason, pot likes to be stored in sexual organs and cause sexual dysfunction.