system
Given the following post, respond as if you're commenting on Reddit:
human
I believe that a functioning drug addiction is not a problem CMV

People who are addicted to drugs but still find meaningful relationships in their lives and society are equally as functioning as people who need meds to treat a mental disorder in order to function on a day to day basis. 

Functioning drug addiction does not affect the lives of the people around the addict, because no one's quality of life is being diminished.

Of course, if the addiction begins to progress to something that DOES begin to affect the quality of life of others, then it should be looked at, but until that point, it should not be considered something that is "wrong" with a person.
gpt
Do you just mean physical dependence?  The medical definition of drug addiction requires it to cause problems for the addict and for use to continue despite those problems.

Assuming yes, then sure- you can be dependent on caffeine without problems.  But there do exist drugs for which dependence inherently caused problems.  For instance, opiates have ups and downs; someone dependent on heroin is going to have times of irritation, times of poor attention, etc.  Tobacco smokers have an increased risk of cancer and fire.  So those would presumably be problems, no?