How Long Does It Take for a Pimple to Form?

2 – 6 Weeks Is the Dermatology Community’s Best Educated Guess

The Essential Info

Even though getting a pimple seems like a simple thing, when we look into the skin and exactly how it happens, many factors come into play. It is also very difficult for dermatology researchers to “catch” a pimple at its earliest stages when it is microscopic and then follow it all the way along.

Therefore, even though it may seem hard to believe, the only evidence we have on how long it takes a pimple to form relies on studies that focus on testing of cosmetic ingredients for their ability to clog pores. These studies have suggested that pimple formation takes anywhere from 2 – 6 weeks.

What This Means in the Real World: When you get a breakout “out of the blue” it may be from something that initiated the pore-clogging process as far back as a couple/few weeks. For instance, if you get a sunburn, you might find yourself breaking out 2 or 3 weeks later. In other words, it’s probably not scientifically sound to blame a breakout on “what you ate yesterday” or “that stress you had a couple of days ago over a test you had to take.” It could be something from quite a while ago.

The Science

• Cosmetic Product Testing Gives Us A Clue (4 weeks)
• Blackhead Removal and Reformation Gives Us Another Clue (2-6 weeks)
• Conclusion From What We Know

Scientists believe that for main factors contribute to acne development:

1. Inflammation: Inflammatory molecules in the skin start off the whole chain of events
2. Skin cell overgrowth: Skin cells overgrow, causing a clogged pore
3. Skin oil (sebum): Skin oil gets trapped in a clogged pore
4. Acne bacteria: Acne bacteria overgrows in the clogged skin oil^1-4

However, researchers have been unable to conduct studies which can accurately observe the timing of each of these four factors because they lack the proper technology to detect the complex, intricate, and microscopic beginning stages of pimple formation.

Cosmetic Product Testing Gives Us A Clue (4 weeks)

The difficulty in investigating the exact timing of pimple formation has led scientists to turn to cosmetic product testing as a way to identify how long it takes for a pimple to form. Certain cosmetic ingredients, called comedogenic ingredients, are known to clog pores and lead to acne lesions. When these ingredients are tested on patients, pimples start becoming apparent after four weeks of treatment. This has led researchers to conclude that in humans, the pimple formation process may take around 4 weeks.⁶

Blackhead Removal and Reformation Gives Us Another Clue (2-6 weeks)

Blackheads are a type of acne lesion that give us another unique window into how long a pimple might take to form. When blackheads are forcibly removed from the skin, they tend to begin to start to reform immediately. Research has found that blackheads will completely reform in 2-6 weeks after removal, suggesting that it may be reasonable to assume that a 2-6 week range is how long it takes for an acne lesion to form.⁷

Conclusion From What We Know (A Range of 2-6 weeks)

Cosmetic ingredient testing shows us pimples starting to rear their heads at about 4 weeks, and blackheads tend to reform 2-6 weeks after removal. So, a good educated guess on how long it takes for a pimple to form is 2-6 weeks.