I was hospitalized with a moderate case of shingles amd was given valtrax, gabapentin, protinics and I also take celexa, tylonal and methodone for pain. I also have used every cream and lotion created to numb this terible pain from the shingles. Now I test positive for cocaine ! What could I have taken or rubbed on to give a cocaine urine ? I was highly embarrased by this ! The gabapenin does nothing at all for pain so if that causes the false psitive it won,t bother me to discontinue it.