Is there a treatment or sanitizer that would be sufficient, in place of frequent handwashing, for someone afflicted with obsessive-compulsive disorder related to cleanliness and cracking of the hands, so that they can be assured their hands are clean and free of germs?

The whispers of Satan (waswas) have greatly affected you. The cure for them is to ignore them and pay no attention to them. Disregard the whispers, no matter what they present to you, and do not wash your hands for anything you mentioned, no matter how strong the whispers become within you. With a little effort, you will get rid of these whispers. Do not wash your hands except when you need to, just like other people do. We advise you to consult a trustworthy psychiatrist.