Frequent flier

[Oralee]

Commonly, someone who is a repeat user of a product or service, regardless of the nature of the business.

In healthcare, someone who is frequently showing up for similar injuries or disorders. Often, this is applied specifically in the world of drug and alcohol [rehabilitation] (rehab) to somebody who has tried to get sober (clean up or [dry out]) but has had frequent relapses. According to current statistics, the majority of addicts (80%) are likely to [relapse] after the first try.

[Britney]

Someone who is constantly [high on] cheap or [unreliable] drugs, such as [Pot] or Crack

[Ernesto]

Somebody who uses [class A] drugs often.

i.e is [frequently] [flying]

[Tanya Shivari]

Someone [who you] [end up] [going home] with after every party.