2. Raynaud's phenomenon  (Trust Mark: Doctor-Reviewed)
Raynaud's phenomenon is a condition in which cold temperatures or strong emotions cause blood vessel spasms that block blood flow to the fingers, toes, ears, and nose. • Reviewer: Mark James Borigini, Associate Clinical Professor of Medicine, University of California, Irvine, Irvine, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

3. Raynaud disease  (Trust Mark: Doctor-Reviewed)
Raynaud disease refers to a disorder in which the fingers or toes (digits) suddenly experience decreased blood circulation. It is characterized by repeated episodes of color changes of the skin of digits during cold exposure or emotional stress.• Author: L. Fleming Fallon Jr., MD, PhD, DrPH