Sometimes it's difficult to tell if your teen is using alcohol or drugs. Parents may worry that their teens are involved with drugs or alcohol if they become withdrawn or negative, although these behaviors are common for teens going through challenging times. It is important not to accuse your teen unfairly and to try to discover why your teen's behavior has changed by telling him or her that you are concerned.

Typically, experts recommend that when alcohol or drug use is suspected, parents look for a pattern or a number of changes in appearance, behavior, and attitude, not only one or two changes. Substance abuse may be a possibility if several of the following signs are present:

• Less attention paid to dressing and grooming
• Loss of appetite or unexplained weight loss
• Red and glassy eyes and frequent use of eyedrops and breath mints
• Decreased attendance and performance at school
• Loss of interest in school, sports, or other activities
• Newly developed secrecy; deceptive or sneaky behavior
• Withdrawal from family and friends
• New friends and reluctance to introduce them
• Lying or stealing
• Disrespectful behavior
• A mood or attitude that is getting worse
• Lack of concern about the future