Pimples and cold sores differ from one another in many significant ways, including causes, patterns of occurence, signs and symptoms.

You look in the mirror and there it is, a bump on or close to your lip, or perhaps on your chin or near your nostril. Given the location, you might wonder whether it's a pimple or a cold sore — or perhaps something else altogether. Examining the substantial differences between pimples and cold sores can help you pin down the likely cause of your blemish or blemishes.


Pimples and cold sores arise from entirely different causes. Cold sores erupt due to an infection with herpes simplex virus type 1, or HSV-1 1. The initial oral herpes infection most commonly takes place during childhood.

Transmission occurs due to direct contact with the virus, which can happen via a kiss from a relative or friend or sharing an HSV-1 contaminated item, such as an eating utensil, drinking glass or facial towel. Cold sores arise due to reactivation of HSV-1, which remains in your body for life once initial infection occurs.

Pimples develop when excess oil and dead skin cells clog pores. The presence of bacteria called Propionibacterium acnes contributes to the development of pimples, or acne. Painless whiteheads and blackheads characterize noninflammatory acne. With inflammatory acne, redness surrounds tender pus-filled pimples, also known as pustules.

Occurence Patterns

Adolescents and adults of any age can get a pimple or cold sore but certain patterns help differentiate the two conditions. Although acne most commonly develops in teenagers, it often persists into adulthood — especially in women.

In some people, acne doesn't develop until early adulthood. As anyone with acne knows, the condition rarely involves one pimple. More typically, pimples tend to occur in crops on various sites involving the face, neck and upper back and/or chest in severe cases.

Because HSV-1 infection most frequently occurs in childhood, recurrent cold sores can start at an early age and occur periodically throughout adulthood. Although a less common scenario, initial HSV-1 sometimes doesn't happen until young adulthood and might go unnoticed due to mild or no symptoms. Therefore, it's possible to develop the first cold sore of your life as an adult.

Signs and Symptoms

According to a November 2010 American Family Physician article, approximately 60 percent of people experience burning, tingling, itchiness or pain in the location where a cold sore is about to erupt — usually within 6 to 48 hours.

The cold sore itself appears as a cluster of tiny, painful, fluid-filled blisters that break open and ooze before crusting over and healing in 7 to 10 days. Cold sores usually occur on your lips or around your mouth. Factors that might contribute to the eruption of a cold sore include stress, fatigue and sun exposure, among others.

Acne pustules typically develop singly rather than in close clusters, though you typically have several pimples at once. You're also likely to have some blackheads and whiteheads at the same time as pustules in various stages of development and healing.

While pustules are usually tender, they are typically less painful than cold sores. Other signs and symptoms that help differentiate pimples from cold sores include:

  • Burning and tingling do not typically occur leading up to the eruption of a pimple.
  • Pimples are pus-filled rather than filled with clear fluid.
  • The cycle of spontaneous oozing and crusting does not occur with pimples.

Skin conditions with a similar appearance and symptoms can mimic cold sores or pimples. Therefore, it's best to see your doctor for an accurate diagnosis if you are uncertain about what is happening with your skin. With a firm diagnosis in hand, your healthcare provider can offer advice regarding the best treatment options for you.