Hi there, Thanks for your query. Lidoderm patches contain Lidocaine, an anesthetic drug. Lidocaine and cocaine are entirely different molecules. Hence, chronic use of lidocaine does not produce positive test for cocaine. However, lidocaine dermal patches, produced in some countries, do use cocaine as a diluent (as has been reported in some studies). It is therefore possible that the Lidoderm patches may have some cocaine as a diluent. I am not sure if the same is mentioned in the constituents enumerated on the pack. Please do check for it. Also, I can t comment on the veracity of the information given on the package of Lidoderm by the manufacturing company. There are several cases all over the world, which have reported as positive for cocaine. Therefore, a false-positive test for cocaine, in patients who have been using Lidocaine dermal patches, cannot be ruled out. Dr. Karanwal