root canal therapy and positive drug screen for cocaine

Do Dentist use any medicines during a root canal or tooth procedure that can cause a positive drug screen for cocaine?

[Jerome Tsang, DDS]

Not to my knowledge, there is nothing that can cause a positive cocaine result.

[Jerome Tsang, DDS]

I did a little research online.  I can't find any scientific articles that specifically deal with positive test results of cocaine from the use of lidocaine (anesthetic) but it is mentioned a few times.   Here's a website with the information posted for false positives.  You may want to contact the writer of the article to see what his/her sources were.

http://www.med.nyu.edu/patientcare/library/article.html?ChunkIID=13837

[Jerome Tsang, DDS]

Sorry... that states novocaine.. which isn't widely used anymore.  I'm not even sure if they even sell it anymore.  But perhaps lidocaine (which is widely used) can also cause a false positive.