After chronic use, the need to administer more of a drug to achieve the same drug effect is known as

Tolerance happens when a person no longer responds to a drug in the way they did at first. So it takes a higher dose of the drug to achieve the same effect as when the person first used it. This is why people with substance use disorders use more and more of a drug to get the “high” they seek.

having the certification could make the person more required to do a certain thing then another.this could also lead to different job offers or opportunities.