Can You Test Positive for Pot If You Don't Smoke It?

If a person has not smoked marijuana, she will not test positive for it, so long as the drug test is accurate, appropriately given and monitored. There are some myths around marijuana and drug tests, however, and understanding these may help to yield accurate results.

Effects

• There is a myth that coming in contact with marijuana may result in a positive drug test due to inhaling the second-hand smoke. Experiments have proven this myth to be untrue. For instance, a study had non-smokers exposed to second-hand marijuana smoke in a small, enclosed room, while eight other people smoked. None of the 90 participants produced test screens positive for marijuana.

Considerations

• Some unexpectedly positive test results for marijuana may be due to the way in which it is metabolized. THC or delta 9 tetrahydrocannabinol, the main ingredient in marijuana, is fat-soluble and can remain in the lungs and brain tissue for up to four weeks. Some people could get a positive result even a month after smoking marijuana.

Warning

• Short-term risks of marijuana use can include impaired thinking, judgment, memory and problem solving ability, as well as increased anxiety and paranoia. Long-term consequences can include respiratory problems, problems with memory and learning and may increase the likelihood of depression and psychosis.