>> once we have oil, we don't know what the ratio is, because it's not going to be what this says, because it just went through this heating process. >> it's trial and error. something we heard from so many medical marijuana patients. >> i do a mixture of thc, cbn and cbd. >> frank had to experiment with many different strains of marijuana to find the right kind to treat his chronic pain and arthritis from an old football injury. >> i have extreme pain in my knee. my body is exhausted, my knee is going to be sore, maybe swelling on the joint, maybe i'll sit down and smoke some flower. >> prescribed painkillers made him sick, so he was desperate to try something new. >> within 15, 20 seconds, the pain just went away, it was gone, absolutely exited the body. >> turns out the most common use for medical marijuana is pain. early studies shows that marijuana reduces inflammation