Also known as fever blisters, cold sores are an inconvenient annoyance for most people, but easily managed. However, cold sores can spell trouble for those with weakened immune systems. Though the sores themselves are a minor irritation, the symptoms of the cold sore virus can also appear elsewhere in the body if your immune system is compromised. Your physician will alert you if your medical condition or treatment is likely to weaken your immune system and if fever blisters are more than pesky sores.
For most of the population, cold sores aren't a serious problem. Eight out of 10 people carry the herpes simplex virus type 1 (HSV-1), which causes clusters of tiny, fluid-filled blisters to appear on or near the lips. For most carriers of the virus, cold sores are the only symptom they experience, and the blisters usually crust over and disappear in about a week.
If you have a weakened immune system, however, the story isn't so simple. As the Mayo Clinic explains, a weak immune response may not control the virus at the cold sore stage, and symptoms may spread to the fingertips, eyes, skin and organs, like the brain or spinal cord.
HSV-1 carriers are at risk of complications from cold sores if they have medical conditions or are undergoing treatment that suppresses the immune system, notes the Mayo Clinic. Patients who take anti-rejection drugs after an organ transplant or are receiving chemotherapy to treat cancer have weakened immune systems, and for them a cold sore could turn into something more serious. Similarly, people with immunosuppressive conditions like severe burn sufferers and people infected with HIV should monitor their health closely if they notice a cold sore. Eczema sufferers are another at-risk category of patients.
Symptoms of a cold sore outbreak often appear before the sores themselves, and you can try to stop the virus in its tracks at this early stage with a range of treatments. If you feel a tingling, burning sensation or see redness or swelling around your lips, ask your physician or dentist about antiviral medications that may prevent cold sores from appearing.
Once the cold sore is there, you can treat it with over-the-counter ointments or hold a cold compress to the area to help the sore heal quickly. To soothe cold sore irritation, apply a maximum-strength oral pain reliever for canker and mouth sores. Remember to wash your hands with soap and hot water before and after touching a cold sore to help prevent secondary infections and reduce the spread of the virus.
Without treatment, a cold sore should disappear within 10 to 14 days. The University of Maryland Medical Center advises that if your immune system is weak, you should contact your physician if you develop a cold sore. Additionally, talk to your family doctor if you've had a cold sore for longer than two weeks and have symptoms like a fever, rash, drooling, difficulty swallowing, or white patches on your tongue and the roof of your mouth.
Are cold sores bad for you? A simple sore isn't a problem by itself, but if the virus that caused it shows up elsewhere in your body, you could become seriously ill. If you think you have a weakened immune system and you feel that familiar tingling that signals a cold sore's appearance, heed your doctor's advice on the best course of action.