Explanation:
Knowing about tolerance can help an unaware individual or an individual in denial realize that their drug use is progressing to a dangerous level and may soon lead to an addiction. Usually, tolerance develops because metabolism of the drug speeds up (often because the liver enzymes involved in metabolizing drugs become more active) and because the number of sites (cell receptors) that the drug attaches to or the strength of the bond (affinity) between the receptor and drug decreases.
