Cosmetic and general dermatologist at Marmur Medical Rachel Maiman, M.D., says nodular acne affects deeper layers of the skin than the average breakout and has a higher risk of scarring coupled with a tendency to persist for weeks to months. Maiman says this type of acne, “often feels like firm knots under the skin and can be found on the face and body.” Engelman adds that nodular acne is firmer than cystic acne and is also more widespread than typical pimples. But if you’re experiencing a breakout that seems to be under the skin, red, inflamed, and/or painful, you’ll want to book an appointment with your local dermatologist for treatment. Another cause to consider is, you guessed it, hormones. “Hormones can cause oil production to increase, which makes breakouts more likely,” Engelman says. Maiman says when androgen (male) hormones increase, so does oil production. “Androgens also can change the chemical makeup of oil, making it thicker, which is more likely to clog pores, as well as a more desirable environment for acne-causing bacteria,” Maiman explains. But when it comes to discerning why some people are more likely to develop nodular acne over others, Maiman says it’s still a mystery. “There does appear to be a genetic component, meaning that, if your parents or sibling had nodular acne, you’re more likely to get it, too.”