The following are some obvious signs that a person may be smoking cigarettes, drinking alcohol, or using other substances. This is not a complete list of signs to look for. If you suspect a particular drug or drugs, get more information on signs of use for those substances.
| Author | Sabra L. Katz-Wise |
| Author | Ralph Poore |
| Editor | Susan Van Houten, RN, BSN, MBA |
| Associate Editor | Pat Truman |
| Primary Medical Reviewer | Kathleen Romito, MD - Family Medicine |
| Primary Medical Reviewer | Michael J. Sexton, MD - Pediatrics |
| Specialist Medical Reviewer | Yifrah Kaminer, MD - Child and Adolescent Psychiatry |
| Last Updated | September 13, 2006 |
WebMD Medical Reference from Healthwise