Acne scars are caused by inflammation of a pimple, which damages the skin. This inflammation causes the body to try to heal that damage by producing collagen. When the skin produces too little or too much collagen, a scar forms.
When too much collagen is produced, a hypertrophic or keloid scar may form. In this case, there is raised tissue build-up in the spot where the blemish existed. Hypertrophic scars are the same size as the blemish, whereas keloid scars cover a larger area.
On the other hand, when too little collagen is produced, an atrophic scar will form. An atrophic scar is where there is indented scarring below the surface of the skin. There are three types of atrophic scars: boxcar scars, rolling scars, and ice pick scars.
There is also a third type of “scar” that can be left behind from acne: post-inflammatory hyperpigmentation (PIH). With PIH, a discolored mark is formed after a blemish heals, due to the skin producing too much melanin in response to inflammation. However, there is no difference to the texture of the skin. While PIH is often lumped together with acne scars, it actually isn’t a scar. That said, PIH responds to many of the same products as actual acne scars (and is actually typically faster to fade).
Severe acne that deeply penetrates the skin (like nodules and cysts) or acne that is left untreated for a longer period of time is more likely to leave a scar or mark. Picking or squeezing a pimple also increases the likelihood of a scar or mark being left behind.
To minimize the appearance of acne scars or PIH, there are a variety of over-the-counter topical products that can be used – we’ll go over some of those below. While you may see some results with these types of products, scars often require professional treatments in order to fully diminish their appearance (particularly in the case of atrophic, keloid, or hypertrophic scars). This can include a chemical peel, dermabrasion, or a laser treatment, which need to be done in-office.
Mild to moderate PIH, on the other hand, will typically respond better to OTC topical products. In fact, PIH often clears up on its own (although topical products will speed up that process).
If you’re interested in using topical products that you can get over-the-counter to treat acne scars or PIH, there are a few key ingredients you should look out for. Alpha hydroxy acids (like glycolic acid, lactic acid, and mandelic acid), vitamin C, retinoids, and azelaic acid are some of the best ingredients for acne scars and marks. You’ll want to find exfoliants, serums, and/or treatments that contain some of these ingredients for the best results.
Consistency and patience is key when it comes to using these products to minimize the appearance of acne scars. You’ll also want to wear sunscreen daily to protect the skin and prevent marks from getting darker.
Best Exfoliants for Acne Scars 
Best Serums for Acne Scars 
Best Vitamin C Serums for Acne Scars 
