Antiviral Creams: What They Are, How They Work, and What Works Best

When you feel that tingling on your lip before a cold sore shows up, antiviral creams, topical medicines designed to stop viruses from spreading on the skin. Also known as topical antivirals, they’re one of the first lines of defense against herpes simplex and other skin viruses. These aren’t magic fixes—they won’t erase the virus from your body—but they can cut the healing time in half if you use them right away.

Most antiviral creams, topical medicines designed to stop viruses from spreading on the skin. Also known as topical antivirals, they’re one of the first lines of defense against herpes simplex and other skin viruses. work by blocking the virus from copying itself. The most common one is acyclovir, a synthetic antiviral drug used to treat herpes infections. Also known as Zovirax, it’s the gold standard for cold sores and has been used for decades. Others include penciclovir and docosanol. Each has slightly different timing, cost, and how fast they work. Acyclovir takes a few days to show results, but it’s cheap and widely available. Docosanol works faster but costs more. Penciclovir lasts longer on the skin, so you don’t have to reapply as often.

These creams are mostly for herpes simplex, a common virus that causes cold sores and genital herpes. Also known as HSV-1 and HSV-2, it’s the main reason people reach for antiviral creams. They’re not meant for shingles, warts, or other skin issues—even though people sometimes try them. Shingles needs oral antivirals like valacyclovir, not creams. Warts respond to salicylic acid or cryotherapy. Using the wrong treatment wastes time and money.

What you won’t find in most stores are creams that actually kill the virus. Some brands claim to use tea tree oil, aloe vera, or lysine—but there’s no strong proof they work better than placebo. The FDA only approves a handful of ingredients for antiviral use on skin. Everything else is a supplement, not a treatment.

If you get cold sores often, you might wonder if cream is enough. For some, yes. For others, especially if outbreaks happen monthly or worse, oral pills like valacyclovir are more effective. Creams work best when you catch the tingling early—before the blister forms. Once it’s open and oozing, the cream won’t help much. That’s why keeping a tube in your bag or medicine cabinet matters.

There’s also the cost factor. Generic acyclovir cream is under $10 at most pharmacies. Brand names like Zovirax can cost three times as much for the same active ingredient. And while some people swear by natural remedies, none have the same track record as FDA-approved antivirals.

Below, you’ll find real comparisons of antiviral creams and related treatments—what works, what doesn’t, and what’s worth your time and money. No fluff. Just clear, practical info based on what’s been tested and what people actually use.