Raynaud's Disease and Home INR Testing

By: Alere Staff

The uncommon circulation disorder known as Raynaud’s Disease, or Raynaud’s Phenomenon, can require some extra precautions for people taking warfarin and testing their INR by the finger stick method. Raynaud’s causes constriction or narrowing of blood vessels in fingers or toes and rarely in the nose, ears or lips. This temporary narrowing allows for decreased blood flow to the area affected, causing the surrounding skin to turn pasty white or blue and feel numb, tingly or even painful. The episodes occur erratically and can be very brief or last for hours. They may affect just a finger or two or all of your fingers. While cold weather is a common trigger for a Raynaud’s attack, emotional stress or anxiety, holding an iced drink or being in air conditioned environments consistently can also trigger episodes. Raynaud’s is more commonly seen in people who live in colder climates or who have a family history of this condition, but the condition effects three to five percent of people worldwide.3

Keeping hands warm by wearing gloves and using pockets for protection in cold weather can be helpful. Some people even wear lightweight gloves when holding iced drinks in the summertime to prevent a Raynaud’s attack. To minimize the impact of symptoms, it is most helpful to run your hands under warm water for several minutes at the first sign of an episode. As warm hands with good blood flow are key to successful finger stick INR tests, it is important to wait for a Raynaud’s attack to pass before poking your finger. Washing your hands with warm, soapy water and massaging them from the palm toward the fingertips while dangling the hand are helpful techniques to practice any time you are testing your INR by finger stick, but especially important if you have Raynaud’s Disease.

For the most part, Raynaud’s Disease does not cause much disruption for individuals who experience episodes, but awareness and appropriate reactions can keep discomfort at bay.

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  1. U.S. National Library of Medicine. Raynaud’s Disease.MedlinePlus. Retrieved Feb. 24, 2016 from the website: https://www.nhlbi.nih.gov/health/health-topics/topics/raynaud/signs.
  2. U.S. Department of Health and Human Services. What Are the Signs and Symptoms of Raynaud’s? National Heart, Lung and Blood Institute. Mar. 32, 2014. Retrieved from the website: https://www.nlm.nih.gov/medlineplus/raynaudsdisease.html.
  3. Yu, W. Expert Q&A: Getting to the Root of Raynaud’s. The New York Times. Apr 29, 2010. Retrieved from the website: http://www.nytimes.com/ref/health/healthguide/esn-Raynauds-expert.html?pagewanted=all