they dont DMSO can be brought at a health food store for $17.00 a jar in 3 formats 99% DMSO liquid 70% dmso cream and 70% gel with aloe vera. The gel is better for people with sensitive skin since DMSO is a solvent but is also a natural cure for herpes,arthritus,sore muscles,and is used to treat AIDS patiants in other countries probly becuse those countrys have a better health system that is not takin over by the major drug corps.