Cold sores, sometimes called “fever blisters,” are inflamed open sores that form around your mouth. These sores are almost always caused by the herpes simplex virus (HSV). There’s no cure for HSV.
Once you’ve had one cold sore, stress, sunlight, or hormonal changes can trigger the virus to activate and give you another one.
There are over-the-counter and prescription remedies that claim to treat the pain and inflammation that cold sores cause. But researchers are beginning to find that the organic compounds found in some essential oils might treat cold sores just as effectively.
This is good news for people that get cold sores, because essential oils might have a lower risk of harsh side effects than pharmaceutical cold sore treatments. Some strains of herpes have developed resistance to the drugs we’ve been using to treat them for years, but essential oils can be effective against these strains.
Essential oils are very concentrated plant oils. They’re not meant to be taken orally — some are toxic when ingested.
Essential oils are meant to be applied topically or inhaled, using an infuser. Always dilute essential oils in a carrier oil, like sweet almond oil before applying to the skin. Usually 3 to 5 drops of essential oil to 1 ounce of sweet almond or olive oil is the go-to recipe.
1. Tea tree oil
Tea tree oil has antiviral, antiseptic, and anti-inflammatory properties. These all come in handy when you need to treat a cold sore. A review on tea tree oil’s uses for skin disorders found that it has a potent antiviral effect on HSV.
You can apply diluted tea tree oil directly to your cold sore using a clean cotton swab, but make sure you dilute it with a gentler “carrier” oil (such as coconut oil or jojoba oil) so you don’t hurt your skin. Don’t use tea tree oil more than twice per day, or your skin may become irritated.
2. Peppermint oil
Peppermint oil is another essential oil with the ability to kill a virus that’s been activated.
A lab study on HSV demonstrated that peppermint oil could calm the symptoms of an activated herpes strain — even strains that are resistant to other kinds of drugs.
Apply diluted peppermint oil directly to the cold sore at the first sign of it for best results.
3. Anise oil
Oil from the anise plant has been shown to help inhibit cold sore infections.
4. Oregano oil
Oregano oil is one of the most popular home remedies for cold sores, and for good reason. Back in 1996, oregano oil’s effects on HSV was found to be substantial.
Rubbing diluted oregano oil on the site of your cold sore with a sterile piece of cotton gauze may help diminish the size and inflammation of your cold sore. It’ll also help heal it more quickly.
5. Lemon balm oil
Lemon balm oil has been determined to inhibit herpes viruses’ penetration of cells by 96 percent for drug-resistant strains, according to a lab study. Further research is examining how lemon balm works on the herpes infected cells.
Since lemon balm oil can penetrate the skin layer and treat the herpes virus directly, you can apply the diluted oil directly to your cold sore up to four times per day.
6. Thyme oil
Thyme oil is a potent agent. It has antiviral effects on HSV, according to a lab study. Of course, if the trigger of the virus is still present — be it stress, a fever, or extended sun exposure — the virus could reactivate even after treatment.
7. Ginger oil
Ginger oil’s components have been found to reduce cold sore infection symptoms in a lab study.
Ginger oil feels warm on your skin and may soothe the irritation from your cold sore. Applying the diluted mixture topically may help your cold sore heal much faster. Consider mixing ginger oil with some of the other oils on this list in a carrier oil.
8. Chamomile oil
A study found chamomile oil to be a very active antiviral agent against HSV. It also proved to help treat drug-resistant strains.
Chamomile oil also soothes the skin when applied. Applying diluted chamomile oil directly to a cold sore as soon as you feel the sore forming is the most effective way to use it.
9. Sandalwood oil
Sandalwood oil is known for its distinct and powerful scent, but its components can also fight the cold sore virus, according to a lab study.
Diluted sandalwood oil can be directly applied to a cold sore when it appears. The strong scent of sandalwood might be irritating to your nose, so mix it with one of the other oils on this list, as well as a carrier oil, if you choose to use this remedy.
10. Eucalyptus oil
Cell structure tests done in a lab revealed that eucalyptus oil could reduce the duration and severity of cold sores. Some people say that eucalyptus oil has a calming scent and a soothing sensation on the skin when it’s applied.
Always dilute eucalyptus oil well before applying, and limit it to four applications per day.
When using essential oils as a topical skin treatment, there are several things you should keep in mind. Diluting the oils that you use for treatment with a nonabrasive carrier oil, such as coconut oil or jojoba oil, will help keep your skin from becoming further inflamed by the cold sore.
Overuse of essential oils on your skin can weaken your skin’s epidermis and make it harder for your skin to repair itself.
Make sure that you don’t have any allergy or sensitivity to the ingredients of your oils before using them. Do a spot test with any essential oil on another part of your skin before you apply it to an open cold sore.
Possible side effects from using essential oils to treat a cold sore range from a moderate stinging sensation to burning or bleeding from the site of the infection. Discontinue use of the oil treatment if at any time you feel like your skin is having a negative reaction.
The U.S. Food and Drug Administration (FDA) doesn’t monitor the production of essential oils. Do some research on the brands and their quality, purity, and safety. You can also speak to a certified aromatherapist.
Remember that the claims that essential oils make aren’t necessarily evaluated by the FDA. If you have persistent cold sores that don’t go away with treatment, you may need to speak with your doctor about preventative treatment methods.
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