I think it is safe to inject Botox if you have scleroderma. In fact, I think that it may help. There have been some studies that used this to help people with Scleroderma and in these cases, the scleroderma symptoms improved.
My assumption here is that you have scleroderma and want to receive a Botox treatment, not be the injector yourself..... So with that being said, I have done Botox injections on numerous patients who have scleroderma. If you'd like to be comfortable with the decision to proceed, consult your rheumatologist or other physician who treats your scleroderma and make certain you see a physician-injector for the Botox.