The most effective thing to put on a cold sore is an antiviral treatment, applied as early as possible. Docosanol 10% cream (sold as Abreva) is the only FDA-approved over-the-counter antiviral for cold sores, and it works best when you apply it at the first tingle, before a blister forms. Prescription options and several other topical remedies can also help with healing and pain, depending on what stage your cold sore is in.
Why Timing Matters More Than the Product
Whatever you choose to put on a cold sore, the single biggest factor in how well it works is when you start. Antiviral treatments are most effective when started within 48 hours of the cold sore forming, according to the Cleveland Clinic. Ideally, you want to apply something during the “prodrome” stage, that initial tingling, burning, or itching sensation you feel before any blister appears. Once a sore has fully blistered and crusted over, antivirals can still help modestly, but you’ve missed the window where they make the most noticeable difference.
Over-the-Counter Antiviral Cream
Docosanol 10% cream is the go-to OTC option. It works by blocking the herpes virus from entering healthy skin cells, which slows the outbreak’s spread. You apply it directly to the affected area five times a day until the sore heals. It’s widely available at pharmacies without a prescription.
That said, the improvement is modest. Clinical trials show that topical antivirals, including docosanol, typically shorten healing time by less than a day compared to doing nothing. That’s not dramatic, but when you’re dealing with a visible, painful sore on your face, even half a day matters.
Prescription Antiviral Options
If you get frequent or severe cold sores, a doctor can prescribe something stronger. There are two main routes: topical creams and oral pills.
Prescription antiviral creams (5% acyclovir or 1% penciclovir) perform similarly to OTC docosanol, reducing healing time by roughly half a day. You apply them five times daily for four to seven days. The real advantage of going to a doctor is getting oral antiviral tablets instead. Oral antivirals work from the inside out, reaching the virus more effectively than anything you rub on the surface. They typically help cold sores resolve within two to three days, and the earlier you take them after symptoms start, the better they work.
For people who get multiple outbreaks per year, a doctor may prescribe oral antivirals to keep on hand so you can start treatment the moment you feel that first tingle.
Pain-Relieving Gels and Creams
Antivirals target the virus but don’t do much for pain. If your cold sore is throbbing or stinging, a topical numbing agent with benzocaine can help. These OTC gels temporarily dull the nerve endings around the sore. Apply them up to four times a day as needed, but not more frequently than that. Products labeled for “oral pain relief” or “cold sore pain” at the pharmacy typically contain benzocaine at various concentrations.
You can use a numbing gel alongside an antiviral cream. Just apply the antiviral first, let it absorb for a few minutes, then layer the pain reliever on top.
Hydrocolloid Patches
Cold sore patches made from hydrocolloid material have become popular, and they serve a different purpose than creams. They don’t contain antivirals. Instead, they create a sealed, moist environment over the sore that keeps out dirt and bacteria, which helps prevent secondary infection. The outer layer forms a barrier against moisture and contaminants while maintaining a slightly acidic environment underneath that discourages bacterial growth.
Patches also hide the sore cosmetically, which is a real benefit for many people. They protect the scab from getting bumped or picked at, and they reduce the chance of spreading the virus through direct contact. One important note: don’t apply a hydrocolloid patch over a sore that’s already infected (showing signs like spreading redness, pus, or unusual warmth), since occlusive coverings can trap bacteria in an already-infected wound.
Petroleum Jelly for the Crusting Stage
Once your cold sore has scabbed over, cracking and bleeding become the main nuisances. Applying a thin layer of petroleum jelly to the sore and surrounding skin reduces dryness and prevents the scab from splitting open. This doesn’t speed up healing in any antiviral sense, but it protects the area, keeps the scab intact, and makes the final days of healing more comfortable. It’s especially useful overnight when your lips dry out.
Zinc-Based Products
Topical zinc is worth knowing about. Zinc salts can irreversibly inhibit herpes virus replication, and zinc-based treatments applied directly to cold sores have been shown to decrease viral load and improve healing rates. You can find OTC zinc oxide creams and zinc swabs marketed for cold sores. A clinical trial using topical zinc oxide with glycine showed effectiveness for oral herpes outbreaks. Zinc products tend to have a drying effect on blisters, which some people find helpful during the weeping stage when the sore is oozing fluid.
Natural Remedies With Some Evidence
Lemon balm extract has the most research support among natural options. A 2012 study found that lemon balm oil can prevent the herpes virus from penetrating cells, which is the same basic mechanism as docosanol. You can find lemon balm lip balms and topical products at health food stores. The evidence is preliminary compared to FDA-approved treatments, but it’s a reasonable option if you prefer a plant-based approach.
Tea tree oil is frequently recommended online, but the research specifically on cold sores is thin. Studies have shown it has general antiviral and wound-healing properties, but there isn’t strong clinical evidence yet that it helps herpes sores in particular. If you try it, always dilute it with a carrier oil first, as undiluted tea tree oil can irritate or burn skin.
Sunscreen to Prevent the Next One
This isn’t about treating a current cold sore, but it’s one of the most practical things you can put on your lips daily. UV exposure is a well-known trigger for cold sore outbreaks. In a study published in the New England Journal of Medicine, patients with a history of recurrent cold sores were exposed to ultraviolet light with and without SPF 15 sunscreen on their lips. When wearing sunscreen, none of them developed a cold sore. Without it, outbreaks occurred as expected. A lip balm with at least SPF 15, applied before sun exposure, is one of the simplest ways to reduce how often cold sores come back.
What Not to Put on a Cold Sore
Rubbing alcohol and hydrogen peroxide are common impulse choices, but both are harsh on already-damaged skin. They can delay healing by destroying healthy tissue around the sore. Toothpaste is another home remedy that circulates online with no evidence to support it and a good chance of irritating the area further. Avoid anything with strong fragrances or active exfoliating ingredients near an open sore.
Also resist the urge to pop or squeeze a cold sore blister. The fluid inside is highly contagious, and breaking the blister open increases the risk of spreading the virus to other parts of your face or to someone else. It also makes scarring more likely.