I have treated s couple of patients with Scleroderma for their upper lip lines, with the approval of their primary care physican and/or rheumatologist. Theresults have been excellent with no side effects, but that can't guarantee you wouldn't develop side effects (unrelated to the scleroderma). You, or your physician who will be treating you with botox, should check with your rheumatologist if it is OK to proceed.
The information provided in Dr. Shelton's answer is for educational purposes only and is not intended to constitute medical advice. The information provided should not be relied upon as a substitute for consultations with a qualified health professional who may be familiar with your individual medical needs. If you are experiencing a medical emergency proceed to your nearest emergency room.
Web reference: http://www.thenyac.com/botox/index.html