Shingles and Your INR

By: Alere Staff

Get your shingles vaccination today” a sign may read as you walk into your local pharmacy, but have you ever considered a shingles vaccination yourself? You might even wonder what shingles (also known as zoster or herpes zoster) actually is and whether or not, as a patient on warfarin, you need to be concerned. The Center for Disease Control and Prevention (CDC) recommends that people aged 60 years and older get one dose of shingles vaccine. So if you are over 60, you might want to think about getting a vaccination, particularly when an estimated one million people get shingles every year in the United States.1

What is Shingles?

If you were a child and had a case of the chicken pox, you may already be familiar with shingles as it is a viral infection caused by the same virus, the varicella zoster virus. About one out of every three people in the United States will develop shingles in their lifetime, with the risk increasing as you get older. Half of all cases occur in men and women 60 years of age or older.1 Shingles occurs in patients that have already experienced a bout of chicken pox. After recovery, the varicella zoster virus stays inactive in your body, reactivating years later in the form of shingles.1

Like chicken pox, shingles is a painful skin disease that can occur anywhere on your body. Most often, it causes pain and a rash on one side of the body, either the left or right side, usually on the face or the torso.2 It most commonly affects older adults and people with weakened immune systems caused by sickness or immunosuppressive drugs. The rash forms blisters that typically start to scab over in seven to ten days. It eventually clears up within two to four weeks.1 Sometimes you can have pain, itching or tingling in the area where the rash will appear before the rash develops. This may happen anywhere from one to five days beforehand.1 Other symptoms you may develop include fever, headache, chills and upset stomach.

Treatment and Prevention

Shingles is not as contagious as the chicken pox. The risk of a person with shingles spreading the disease is even lower if they keep the blisters covered as spreading is caused by contact with the blister fluid itself.2 However, your risk of getting the virus is greater if you have never had chicken pox. If you’ve never had chicken pox, though, the virus transmitted by shingles will result in the contraction of chicken pox.1,2

If you do develop shingles make sure you prevent spreading the sickness to anyone by keeping your blisters covered until they have scabbed, avoiding touching or scratching the rash, washing your hands and staying away from people who’ve never experienced chicken pox or have weakened immune systems.

If you have shingles and are on warfarin, let the doctor treating you know. Some of the pain medications used to treat shingles can affect your INR and your doctor may want you to test your INR at home more frequently. As always, it is best to communicate with your warfarin nurses and doctor whenever there is a change in your condition or the medications you are taking.

The only way to reduce the risk of shingles is to get the vaccine. Even if you have already experienced shingles, you can get it again. Make sure to talk your doctor before getting the vaccine. This is why it is so important to get vaccinated.

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  1. Centers for Disease Control and Prevention (CDC). Shingles (Herpes Zoster). National Center for Immunization and Respiratory Diseases, Division of Viral Diseases. May 1, 2014. Retrieved from
  2. NationalInstitutes of Health. Shingles. NIH Senior Health. April 2013. Retrieved from website