Hi, I Have An Individual Who Has On Going Amphetamine

Hi, I have an individual who has on going amphetamine use but has on going hallucinations about having bugs crawling on her or coming out of her hair, she states she sees things like thread or pieces of dirt that she thinks are parasites etc. Her hands and feet swell up. She has blisters on the ends of her finger tips. She doesn't relate the amphetamine use with the hallucinations. She has been tested for bacteria, parasites and everything but all are normal. Any suggestions?