Drug addiction is a problem that can occur in both adults and in teens. Because of the deadly effects of drug addiction, it is necessary that drug addiction be detected as early as possible. In laboratories, the use of drugs may be detected through urine or blood tests. Other body tissues may also be used in performing the drug test. In most cases, the body is cleared of the drugs in just three days. However, there are some drugs that stay in some body organs for several years.
Since not everyone can be subjected to drug tests, there are other signs that you can watch out for, which could be signs of drug addiction.
Sudden loss in weight
If the person has not been sick and is not on a diet, a sudden drop in weight may make you suspect a person of using prohibited drugs. This is just the general rule, though. Keep in mind that there are also some drugs that may cause the person to become hyperactive and to eat much more than necessary.
Changes in behavior
People who are addicted to drugs may become secretive. They may favor hushed conversations and will try to keep their things from being touched by other members of the family. Drug addicts are also irritable and suspicious of the actions of the people around them. Depending on the drug that is being abused, some drug users may be excessively energetic (that they tend not to sleep) while there are others who are depressed (that they tend to sleep the whole day).
You may also notice a change in the peers of the person who is starting to use drugs. He or she may no longer mingle with the same group of friends and secretly start associating with people of dubious identities.
Drug addiction does not only cause a problem for the drug addict but also for his or her family and the community. By identifying the signs of the addiction, the life of the drug addict is saved before the addiction becomes more severe.

A counsellor who specializes in Addictions can help you better understand your problem, and how to work through it.