Tolerance: Over time, a need for more drugs to feel the same effects. Do they use more drugs now than they used before? Do they use more drugs than other people without showing obvious signs of intoxication?
Withdrawal: As the effect of the drugs wear off, the person may experience withdrawal symptoms: anxiety or jumpiness; shakiness or trembling; sweating, nausea and vomiting; insomnia; depression; irritability; fatigue or loss of appetite and headaches. Do they use drugs to steady the nerves, stop the shakes in the morning? Drug use to relieve or avoid withdrawal symptoms is a sign of addiction. In severe cases, withdrawal from drugs can be life-threatening and involve hallucinations, confusion, seizures, fever, and agitation (medical attention may be necessary).
Loss of Control: Using more drugs than they wanted to, for longer than they intended, or despite telling themselves that they wouldn’t do it this time.
Desire to Stop, But Can’t: They have a persistent desire to cut down or stop their drug use, but all efforts to stop and stay stopped, have been unsuccessful.
Neglecting Other Activities: Spending less time on activities that used to be important to them (hanging out with family and friends, exercising or going to the gym, pursuing hobbies or other interests) because of the use of drugs.
Drugs Take Up Greater Time, Energy and Focus: They spend a lot of time using drugs, thinking about it, or recovering from its effects. They have few, if any, interests, social or community involvements that don’t revolve around the use of drugs.
Continued Use Despite Negative Consequences: They continue to use drugs even though they know it’s causing problems. The person may realize that their drug use is interfering with ability to do their job, is damaging their marriage, making problems worse, or causing health problems, but they continue to use.