Cold Sore vs Pimple: How to Prevent, Treat, and Tell the Difference Between Them - Allure

Dr. Friedman adds that all acne is inflammatory, and when inflammation brews around the sebaceous gland (a small gland in your skin responsible for secreting oil), it causes the area to swell and produce more sebum, resulting in a pus-filled pimple. Those with hormonal acne also experience pimples, most often around the jawline, during their menstrual cycle or when their hormones are fluctuating.

Unfortunately, pimples don't have the same tell as cold sores — you can't always feel them coming. But Dr. Evans says an acne spot treatment with benzoyl peroxide can help prevent brewing pimples from reaching the surface.

How do you know if it's a pimple or a cold sore?

A cold sore at the edge of a person's lip.

Visually, cold sores and pimples can look quite similar — red, fluid-filled bumps that appear along your lip line — and can easily elicit some confusion in someone who's suffering an acne or cold sore breakout. Both breakouts tend to come with some swelling and inflammation of the lip (hey, free lip lift!) which can be uncomfortable.

The simplest way to determine whether you have a pimple or a cold sore is to pay close attention to the warning signs. If you feel a tingling or burning sensation before the blemish even emerges, that's your body's way of telling you a cold sore is coming. While pimples may be tender or cause discomfort, they don't come with the same tingling, burning sensation that often accompanies a cold sore, says Dr. Shah.

From there, "location is helpful with distinguishing acne from cold sores," says Dr. Friedman. "While there can sometimes be free-standing oil glands on the lips, called fordyce spots, typically there are no oil glands and therefore acne can't occur on the actual lip itself." So, if you're dealing with a blister on the skin of your lip, you might have a cold sore. And while pimples can occur anywhere on the body, cold sores caused by HSV-1 are restricted to the mouth area.

Can cold sores be a single bump like a pimple?

It's highly unlikely that a single, stand-alone bump is a cold sore. Cold sores appear as red, fluid-filled blisters, which Dr. Shah says usually come in clusters on or around the lips. The cluster can sometimes look like a small group of pimples, but pimples are unlikely to appear in such clusters or directly on the vermilion line.

Can you squeeze a cold sore like a pimple?

It can be tempting to squeeze a cold sore blister in the same way you might squeeze a pimple (wait, don't do that either!), but skin experts say it's not a good idea. "Traumatizing a cold sore [by squeezing it] can make it worse," says Dr. Evans, "or it can become infected." Squeezing a cold sore turns a blister into an open wound, leaving you more susceptible to bacterial infections and more prone to scarring. Beyond that, cold sores are highly contagious — popping a cold sore can spread the virus and increase your risk of passing it to someone else.