Using a drug or substance regularly makes a person addicted to that thing. For example, regular smokers need a cigarette every next minute or hour. Similarly, if you seek an escape from PTSD by using alcohol or any other drug, chances are very high that you’ll get addicted to that particular substance. People who are addicted to a substance need it for doing almost everything. If you’re addicted to weed, you will need it throughout the day to function. Otherwise, your brain will refuse to function properly, and you may lose focus.