Cold sores: symptoms, treatment and how to avoid spreading them

Cold sores are also called fever blisters or oral herpes. According to MedlinePlus, they are almost always caused by herpes simplex virus type 1 (HSV-1), and most people in the U.S. have it by age 20. After the first infection, the virus stays dormant in the nerves of the face and can come back. In children, a first cold sore usually spreads through kisses or shared cups and utensils.

It spreads through direct contact with a sore or with the person (a kiss, for example) and by sharing utensils, towels or razors. It can spread even when no blisters are visible. It is not the same as canker sores, which are not contagious, or shingles, which is caused by a different virus.

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A cold sore outbreak is handled in a doctor visit, the same price for every age, with no membership. A refill of a medicine you already take (non-controlled) is a follow-up visit. You pay by card when you request the visit, and you get a full refund if the clinic can’t see you. See all prices.

According to MedlinePlus, the most common symptoms are:

• Itching, burning or tingling on the lips before blisters appear
• Small fluid-filled blisters on or around the lips
• Blisters that break open and crust over
• With the first outbreak, sometimes a sore throat, fever and swollen glands

Cold sores go away on their own in 1 to 2 weeks. Prescription antivirals work best when started at the first warning signs, the tingling or burning, before blisters form. According to MedlinePlus, over-the-counter creams help only a little. What does help: ice or a cold cloth, salt-water rinses, and acetaminophen or ibuprofen for pain, as the label directs.

Valacyclovir (Valtrex) and acyclovir for cold sores. These are prescription antivirals used for cold sores. According to MedlinePlus, valacyclovir is started as soon as symptoms appear, so it helps to book at the first tingle. If you have kidney disease or a kidney transplant, tell the doctor before she prescribes it. If you get outbreaks often, the doctor reviews with you whether suppressive therapy with valacyclovir is right for you. If appropriate, the doctor prescribes and we send your prescription to your pharmacy.

Outbreaks can be triggered by menstruation or hormone changes, fever, stress and the sun. Puerto Rico’s sun is strong all year: use a lip balm with sunscreen.

• Don’t touch or pop the blisters, and wash your hands if you do touch them.
• Don’t kiss or share utensils, glasses, towels or razors while you have blisters.
• Avoid oral sex during an outbreak.
• Don’t kiss newborn babies while you have a cold sore.

According to MedlinePlus, see a doctor if symptoms are severe or don’t go away after 2 weeks, or if your immune system is weakened by an illness or medicines.

Get in-person care the same day if you have blisters near your eyes, because herpes in the eye can cause scarring; if a newborn has been in contact with someone with a cold sore and develops blisters or seems unwell, because herpes in newborns can be serious; or if a person with eczema has a blistering rash that spreads quickly. For your safety, call 911 if a baby has a seizure, won’t feed or has trouble breathing.