Most disorders start with experimental use of a substance and progress to occasional social use. For others, use becomes more frequent.
The risk of developing a disorder and how fast a person becomes dependent varies by substance. Some substances have a higher risk and cause dependency more quickly than others.
As a person begins to misuse substances, they require more frequent use or larger doses of the substance to get high. They may need the substance just to feel normal.
As their substance use increases, it becomes more difficult to go without, and attempts to stop using may cause intense cravings and make them feel sick.
There are many signs, both physical and behavioral, that indicate substance misuse. While there are different manifestations for different substances, there are some general indications that a person is misusing; including mood swings, withdrawal from family and friends, a marked change in personal grooming, a loss of interest in their favorite activities, and changes in sleep patterns.