Drugging/drinking dreams are, indeed, quite common. They can be disturbing, especially if we interpret them as impending relapse or some hidden desire to do so.
Remember, dreams are just our subconscious firing a lot of info around. They're not harbingers of the future or some implied way of releasing our inner desires.
Many people, addicts and non-addicts alike, have disturbing dreams...of death, odd sex dreams, etc. They aren't harmful.
On awakening from one of these dreams, it can be helpful not to dwell on them. Get into your daily routine ASAP and let them drift away. Talk them out if you feel you need to, but it may be best to let them go.