Everything You Need to Know About Fever Blister Remedies, Causes, and More

How long does a fever blister last?

A fever blister, or cold sore, can last from 10 to 14 days. It can may also show up on the tongue or gums. Fever blisters usually occur in groups and cause red, swollen, and sore wounds. They may release a clear fluid that scabs over after a few days. During this time, fever blisters are contagious.

If you find yourself having an outbreak, know that it’s very commonplace. Worldwide, more than 90 percent of the adult population has one or both forms of this virus (HSV-1 and HSV-2). In the United States, about 65 percent of the population has HSV-1. A flare-up can heal without treatment, but there are effective ways to help relieve the pain and promote healing.

Natural home remedies for fever blisters

Essential oils and topical treatments can irritate your skin. So when it comes to natural remedies, you should always perform a patch test before use. Also, you’ll need to dilute essential oils with a carrier oil (vegetable or nut oil). The ratio is about one drop of essential oil per teaspoon of carrier oil.

Use a clean cotton swab or pad when applying these remedies, which helps avoid contamination and reinfection.

  1. Press ice on it

Ice can help treat inflammation by reducing blood flow to the area. It also numbs the area so that there’s less pain. But this treatment is only temporary.

How to use: To treat a cold sore, wrap an ice pack with a towel or cloth. Place it on the cold sore for at least 5 minutes. If it doesn’t cause too much pain, you can apply an ice cube directly to the cold sore.
2. Apply lemon balm (Melissa officinalis)

One 2012 study found that Melissa officinalis could affect how the virus attaches to host cells.

How to use: Apply a cream, ointment, or lip balm containing lemon balm to the affected area several times per day. You may also put diluted essential oil on a cotton ball and hold it on the sores for a few minutes. Continue using lemon balm for a few days after your sores have healed.

You can also drink lemon balm tea, but avoid taking it with sedative medications as it may cause drowsiness.
3. Take L-lysine

L-lysine is an amino acid that can help shorten the duration of a fever blister. People report benefits from taking this supplement as a preventative and treatment. According to Harvard Health Publications, lysine can hamper the amino acid that promotes the growth of the fever blisters, but there needs to be more recent studies to conclude its effectiveness.

How to use: Research doses range from 500 to 3,000 milligrams. Follow the recommendation on the package.
4. Try zinc therapy

Zinc is an essential enzyme that helps wounds heal, and topical zinc may help with your fever blisters. One 2001 study found that a zinc oxide and glycine cream shortened the duration of cold sores compared to a placebo cream.

How to use: A 2005 pilot study saw reduced recovery time when their participants took zinc sulfate supplements. They took 22.5 mg twice a day every other month. For topical treatments, you’ll want to apply the zinc cream four times a day. You can find zinc cream on Amazon.
5. Try oregano oil

On a cellular level, oregano oil is shown to inhibit different animal and human viruses, including herpes.

How to use: Apply diluted oregano oil to a cotton ball and hold it on the affected area for as long as is comfortable. Repeat several times throughout the day, and continue treatment until your blisters heal completely. Oregano oil is available online on Amazon.
6. Dab licorice extract

Licorice root is gaining popularity as a treatment for cold sores. A 2014 cell study found more evidence of licorice’s antiherpetic activity, but its effects on humans still need more research.

How to use: You can apply diluted licorice extract on your fever glister with a cotton swab or finger tips. If you’re using pills, make it into a paste with coconut or almond oil and apply to the affected area. Talk to your doctor before taking licorice root orally as it may cause unintended side effects.
7. Use tea tree oil

A review of tea tree oil studies suggest that it’s an effective antiviral treatment. It may also help to speed up the healing process and prevent plaque formation.

How to use: Use topically by adding diluted tea tree oil to a cotton ball. Dab it on the sore spot several times per day, and continue treatment until your skin is completely healed. You can find therapeutic grade tea tree oil on Amazon.
8. Apply witch hazel

A 1996 study found witch hazel to be effective in fighting the herpes virus and in reducing inflammation. Witch hazel is also an astringent and dries out the area, which may help with healing.

How to use: Apply witch hazel (Thayers Organic) directly to the skin using a moistened cotton ball. Hold it onto your skin using light pressure, and be careful not to rub. Continue treatment until your skin is fully healed.
9. Use apple cider vinegar

Some people report benefits using apple cider vinegar (ACV) for fever blisters. While there is no evidence for ACV and herpes, research shows that ACV has anti-infective and antifungal properties that may help.

How to use: Use a cotton ball and apply diluted ACV to the affected area several times per day. You can hold it there for a few minutes at a time. Continue treatment until healed.

ACV is unsafe to consume in large amounts and can cause skin irritation.
Risks and warnings

The above remedies may not be safe for you to use if you’re pregnant or nursing. Avoid using essential oils on children or older adults. Always begin with a small amount of your chosen remedy to see how your skin reacts, and discontinue use if it irritates your skin with a prolonged burning sensation.

Talk to your doctor if you plan on taking oral supplements. Herbal remedies and supplements can interact with any medications and cause unintended side effects.

Prescription medication for fever blisters

Without treatment, a fever blister can last as long as four weeks. Unlike natural remedies, antiviral drugs are proven to speed up the healing process. These drugs include:
Treatment Effect
acyclovir (Xerese, Zovirax) reduces healing time by 0.5–0.6 days and pain by 0.3–0.4 days
valacyclovir (Valtrex) reduces healing time by 1.8–2.2 days
famciclovir (Famvir) reduces healing time by 1 day
penciclovir (Denavir) reduces healing time by 0.7–1 day and pain by 0.6–0.8 days

For severe cases, your doctor can prescribe medication in the form of a pill, cream, or injection. According to the Mayo Clinic, pills, such as valacyclovir and famciclovir, are more effective.

What causes fever blisters to appear?

The herpes simplex virus (HSV-1) causes fever blisters, also known as cold sores, and oral herpes. They can spread or infect other parts of the body, including the genitals. Symptoms don’t always appear right away. The virus can also lie dormant in your system and can recur at any given time. Generally, an outbreak occurs when you’re not completely healthy.

Certain triggers may activate the virus and cause an outbreak. These include:

injury or trauma to the afflicted area
dental procedures
hormone fluctuations
extensive sun exposure

Lowered immunity and other health conditions that can also trigger an outbreak include:

high-grade fever
muscle aches
sore throat
swollen lymph nodes

Risk factors
What increases your risk for fever blisters?

A fever blister outbreak may be a sign of poor nutrition or of an immunity disorder. Fever blisters may accompany other medical conditions that compromise your health.

People with the following conditions are prone to fever blister outbreaks:

weakened immune systems
severe burns

In more serious cases the virus can spread to the hands, eyes, or the brain. If your blisters spread to another part of your body, it’s crucial for you to visit a doctor.

When to see a doctor

Schedule an appointment with your doctor if your fever blisters don’t show signs of healing after six days. You should also visit your doctor if you have:

severe pain
blisters near your eyes
difficulty eating or swallowing
a weakened immune system
frequent outbreaks
a severe outbreak

Your doctor can also help you identify outbreak triggers or the root cause of the outbreaks. They will also determine if the outbreaks increase your risk for other complications.