Cold Sores Causes and Prevention

Cold sores are those annoying blisters that form on your lips and seem to stay there. They are caused by the herpes simplex virus, which is very contagious and affects many kids when they are young.

Cold sores, also called fever blisters, can happen to people of all ages. People all over the world have the virus that causes cold sores.

A big, red, swollen, and oozing blister on your face can be pretty embarrassing. These blisters can come back, which is bad news. Still, there is hope: you can lessen how bad and often your attacks are. To do this, you need to know where cold sores come from and how to avoid getting them.


An infection causes cold sores with the herpes simplex virus (HSV). The virus HSV-1 causes most cold sores. Most of the time, HSV-2 is the cause of genital herpes. With close contact, like kissing or oral sex, either can spread to the face or genitals. Sharing dishes, razors, and towels could also cause the herpes simplex virus 1 to spread.

Because the herpes simplex virus spreads so easily through body fluids, cold sores are most likely to spread when blisters leak. For the virus to spread, it does not need blisters. Even though they have the herpes simplex virus, many people never show signs of it.

Herpes simplex virus can stay dormant in nerve cells of the skin for years after the first infection, causing a cold sore to come back at the site of the first blister. Some reasons why it might happen again are −

  • Fever or infection from a virus

  • Changes in hormones, like those that lead to menstruation

  • Stress

  • Fatigue

  • Getting too much sunlight and wind

  • Adaptations to the immune system

  • Skin injury


Fever blisters, more commonly called cold sores, are fluid-filled blisters that appear on or around the lips and are both annoying and unpleasant. Shedding light on the herpes simplex virus as the root cause (usually, type 1).

Cold sores will heal on their own in 7–10 days. Still, antiviral drugs can greatly shorten the time it takes to get better. Taking famciclovir (Famvir) or valacyclovir (Valtrex) for just one day can cut two days off the time it takes for cold sore symptoms to show up.

It's best to take these medicines by mouth when you feel the first signs of a cold sore, like burning or tingling. Using an antiviral lotion several times a day for five days takes a lot of time and doesn't work well.

Both valacyclovir and acyclovir (Zovirax), antiviral drugs, can be taken daily to prevent getting the herpes simplex virus. The chance of getting another cold sore is cut by about a third. Staying out of the sun and wind is another good way to lower your risk of getting a cold sore. If being in the sun makes you feel bad, you can avoid getting sunburned by putting on sunscreen. Even though this is what most people think, there isn't much evidence that taking extra lysine will protect against cold sores.

To lessen the likelihood of developing a cold sore after being exposed to HSV-1, try the following −

  • Stay Healthy − Cold sores are sometimes called fever blisters because they appear in response to a high body temperature.

  • Sleep well − The immune system is further compromised by exhaustion, increasing the likelihood of illness.

  • Always use a sunscreen-infused lip balm − Lips that are not exposed to sunburn are less likely to get an eruption.

Be cautious near infants if you have a cold sore. Don't kiss a newborn until your cold sore has completely healed, and remember to wash your hands frequently.


The virus that causes cold sores could spread to other parts of the body and make things worse for some people.

  • If a person with a cold sore touches their eye, they could contract an infection caused by the herpes simplex virus (HSV-1). HSV keratitis is an infection of the cornea that can be very dangerous if it is caused by herpes simplex virus type 1. Blindness can result from a serious case of HSV keratitis.

  • Oral intercourse can transmit HSV-1 to the genitalia, where it can cause sores like warts or ulcers on the genitalia or anus. Nevertheless, HSV-1 is not the same as HSV-2, the sexually transmitted virus responsible for most genital herpes cases.

What can you do to Ease the Pain of Cold Sores?

Cold sores are bothersome, but you can care for them at home. Some of the ways are −

Apply Ointments and Creams that you can get at the Store.

These treatments can reduce how long it takes to get better and how bad your symptoms are. You should use them as soon as you notice the first signs of a cold sore to get the best results.

Take Painkillers.

You can ease the pain of a cold sore by putting a topical analgesic on it. Your doctor may recommend lidocaine or another product you can buy over the counter. Acetaminophen and ibuprofen, painkillers, can also be taken by mouth.

Use an SPF Sunscreen and lip Balm.

A cold sore needs to be kept out of the sun while it heals. Also, using an SPF 30 lip balm daily might help stop new outbreaks.

Eat less Acidic Meals

Cold sores can worsen when you eat acidic foods like orange juice, tomatoes, and pickles.

Apply a cold Compress.

A cold, wet washcloth can help make a cold sore less painful. Use it for short periods at different times of the day. Don't forget to wash the towel you used if you don't want to give someone else a cold sore.


Doctors don't always know what makes a cold sore come out. Sometimes, the virus can cause genital herpes and cold sores.

Cold sore blisters that appear on the mouth, lips, or nose crust over after 3 days, and the itching and tingling feeling goes away.

Most cold sores heal completely in two weeks and don't leave any scars. Even if you can't see the blisters, they can spread quickly. Direct physical contact between people is needed for the virus to spread. This includes kissing, skin-to-skin contact, and sharing drink containers, eating utensils, towels, or toothbrushes with a person who has a cold sore.

Updated on: 04-Apr-2023


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