A person I know believes that one can become acclimated to prescription drugs (or even over the counter) so that they quickly become useless.
I’m looking for authoritative references to the issue of development of drug tolerance in the human body. How quickly does it happen? Are some types of drugs more likely to reach tolerance level in most humans more quickly than others? If so, which ones? Is there an average number/amount of drugs the person must take before becoming tolerant?