When you get a cold sore, which is also called a fever blister, you want it to go away as quickly as possible. These weepy red sores that pop up, seemingly at random, are unsightly, uncomfortable, and embarrassing for most people.
The good news is that you can treat cold sores using topical medication in cream, ointment, or a patch, so they disappear faster.
We make it easy for you to participate in a clinical trial for Cold sores, and get access to the latest treatments not yet widely available - and be a part of finding a cure.
Humans are susceptible to several types of mouth lesions, inside and out — cold or canker sores, thrush, or a rash. It's easy to confuse a cold or canker sore as they look similar — painful, swollen red bumps with whitish patches.
The primary difference between cold and canker sores is that cold sores are caused by a virus and are external, are usually a little oozy, and can pop up around the mouth and on the lips. Whereas a canker sore, or mouth ulcer, is the result of mouth trauma (biting your cheeks, dental work), allergy, or other triggers and is not contagious.
In simple terms, cold sores are the external manifestation of a virus. What causes cold sores? In this case, the virus is herpes simplex 1 or HSV-1. This virus is one of about a hundred variants of herpes and one of eight that affect humans.
The virus is spread when someone with the HSV-1 virus — and in the US, about 90% of the adult population — has skin-to-skin contact with another person. Since the herpes virus lives forever in your body, you can transmit the disease even if you're not having an outbreak.¹
The best way to prevent spreading HSV-1 is not to share lip balm, razors, or even forks and spoons if you have a flare-up.
Once you have the virus, some triggers can reactivate it. Teens are most likely to get the virus, and outbreaks subside as they age. Cold sores in adults over 35 are rare.
These are some of the factors that can cause a recurrence of the virus.
Stress or fatigue
Illness, e.g., cold, flu, or fever
Injury to the lips or mouth
Dental work or cosmetic surgery
Hormonal changes (getting your period is a particular culprit)
Children and people with compromised immune systems are at the highest risk for the HSV-1 virus.
The lifecycle of a cold sore
Typically, you'll see the initial symptoms between two days and three weeks of exposure to the virus. Here are the signs of an outbreak.
The skin around your mouth becomes sensitive and may burn, itch, or have a tingling sensation.
A blister, or blisters, pop up around your mouth (anywhere from under your nose to below your lips and the corners of your mouth).
The blisters open up and turn into open sores.
The sores weep fluid for a few days, then dry up, turn crusty, and start to heal.
Most cold sores heal completely within three weeks and rarely leave scars.
Some people have other symptoms that mimic the flu — body and headaches, fevers, or swollen glands. Others may not even get the cold sores and not know they even have the virus. Their bodies just react differently.
The sneaky thing about the herpes virus is that it goes dormant, living in the nerve cells under the skin, so anyone infected can transmit the disease at any time. It is a highly contagious disease.
A cold sore will heal on its own, but most people would rather not have an unsightly blister a minute longer than is absolutely necessary. There are a variety of remedies for a cold sore, ranging from common-sense advice to a prescription from your healthcare provider.
Here are some basic tips for managing a cold sore.
Wash your hands with soap and warm water before you apply any topical treatment.
Gently dab the cream or ointment on the blister; don't rub it in.
It's tempting to scratch at an itchy blister, but avoid the temptation, as this can lead to scarring. In this case, sharing is not caring. Do not let others use your cold sore medication.
If it hurts to brush your teeth, use an antiseptic mouthwash for a couple of days or toothpaste for sensitive teeth.
Avoid foods that will irritate the blister — anything too acidic or salty.
Drink lots of water or other non-alcoholic fluids to stay hydrated.
If there's any good news about cold sores, it's that they are so prevalent in the society that there are numerous treatments and medications available over the counter at pharmacies and other stores.
These usually come in a cream or ointment form, so you apply a dab or two directly to the infected area. Here's a pro tip: use a cotton swab to apply the cream instead of your fingers. You still need to wash your hands before and after, but the less touching, the better.
The trick to ensuring the success of an OTC treatment is to start it early — at the first sign of tingling or tenderness that indicates a blister is forming under the skin.
When scouring the pharmacy looking for an OTC medication, there are certain ingredients that you should look for.
Drying agents: Calamine lotion, zinc oxide, witch hazel, and Domeboro all act to dry out the fluid in the blister.
Topical steroids: Hydrocortisone or another anti-inflammatory agent can help with itching, swelling, and redness.
Topical gels and ointments: Vaseline, plain Chapstick, and Aquafor are applied to the blister to keep out bacteria that can irritate the sensitive tissue. Topical hydroxypropyls are cellulose-based gels that stick to the sore and keep out external irritants.
Sunscreen is an important part of your cold sore treatment regimen. Exposure to the sun can worsen a cold sore outbreak, so any lip balm or sunscreen should be at least an SPF 30. For maximum protection, keep it in your pocket year-round.
Whichever medication you choose, the key is to start using it at the first sign of symptoms.
If your cold sores recur frequently, your doctor may prescribe an antiviral cream or tablet to speed up the healing.
Docosanol, penciclovir, or acyclovir are the most common creams applied directly to the sore using a cotton swab, just like the OTC creams.
Your doctor may prescribe oral antivirals for more severe cases, including acyclovir, valacyclovir, or famciclovir.
If these medications don't work, there are IV options for HSV-1 — typically aciclovir. However, these are usually reserved for those who are severely immunocompromised.
A recent international clinical study found that medical grade honey (MGH) outperformed prescription antivirals, and participants in the study would prefer this MGH to traditional pharmaceuticals.²
The advancement of hydrocolloid technology has made cold sore patches a viable treatment alternative when you have an outbreak. These patches are occlusive, absorbent wound dressings that promote healing of the lesion, as well as relief from symptoms and discreet hiding of the sore.
In simple terms, the manufacturers put HSV-1-fighting chemical compounds into a high-tech material that's transparent and adheres to the skin surrounding the cold sore. The patch has two jobs — to continuously apply medication to the sore and keep out bacteria and other irritants and to somewhat hide the blister itself.
The important thing to know about patches is that they are not prescription medication; there are no antivirals present. The patch's main goal is to make the environment favorable for the cold sores to heal.
At present, there are two types of patches, which include:
hydrocolloid gel patches
film forming serum, Herpatch Serum
A 2020 study published in Scientific Reports compared the effectiveness of the Herpatch and Compeed patches against Zovirax cream (an antiviral cream) and found that across the board, Herpatch participants had the best results in symptom relief and healing.³
The downside to Herpatch is that the area around the lesion dried out to an uncomfortable degree, while the Zovirax group found that the cream wears off faster than the patches. An issue with the Compeed patch is that the patch margins peel off while the wearer is eating or drinking.
The biggest takeaway from this study is that there was no noticeable difference in healing between the non-medicated patches because while one provides the antiviral medication, the others provide an optimal healing environment.
The Compeed patch is popular in the US. In Cold Sore Study Group research, the team used this patch to compare the efficacy of dermal patches to a 5% acyclovir cream. The results were similar to the study that compared Compeed to Herpatch and Zovirax; the sores cleared up about the same times, but participants preferred the patch for cosmetic reasons.⁴
If you're using a patch, you should know a few things about how and when to apply it for maximum results. You can go about your daily life with a patch, wear makeup and lipstick, and eat and drink.
These patch usage tips are courtesy of Compeed.⁵
You should always wear the patch until the sore is drying out. You should change it to a fresh one every 12 hours. Constantly applying the patch is necessary for quick healing.
When using a patch to treat a cold sore, the sore should go away in about ten days.
Cold sores differ among people. Some people can be exposed to the virus and never get a cold sore, while others can get cold sores several times a year.
If you know you've been exposed to HSV-1, you should take steps to heal the blisters as soon as possible, and if your home treatments don't heal the blister, see your doctor.
If your immune system is compromised, you should see your doctor. For some people, the complications from cold sores far outweigh the impact of the virus itself.
Immuno-compromised people — for example, if you have HIV or are undergoing chemotherapy — are at high risk of further complications.
The HSV virus can infect the area if you have eczema, any cuts, or other skin infections. If the virus spreads to your eye (this happens when you touch your eye area after you've touched a blister), you can develop herpetic pink eye, which can cause blindness if you don't see your doctor.
Occasionally, untreated HSV can spread to the brain, causing inflammation and swelling (encephalitis).
Cold sores come and go but happen less frequently as you get older. The virus lives in your body forever.
Many people are embarrassed by cold sores, but remember that almost everyone carries the virus. When you have an outbreak, try treating it with an OTC patch or a topical cream. Consult your doctor first to ensure you're not in a high-risk category, and follow their instructions for healing and avoiding a recurrence.
Oral herpes | Johns Hopkins Medicine
Cold sore | Compeed
Chapter 68 herpesviruses (1996)
Cold sores: Who gets and causes? | American Academy of Dermatology Association
Herpes simplex virus | Nationwide Children's
Cold sore | NHS Inform