Beyond that, problems can also arise from not cleaning your skin or the roller properly before each use. "Rubbing alcohol can be used to clean at-home devices, but in order to kill bacteria, the alcohol must evaporate to be effective," says Dr. Kappel. "More importantly, make sure the skin is clean prior to using the microneedling tool to avoid infection, acne, and cysts from forming." Even if you take all precautions, though, your skin still may not react well. "Sometimes, the traumatisation that these rollers cause to the skin leads to swelling, which can temporarily make wrinkles look better, but as the swelling goes down, the wrinkles reappear. Something called post-inflammatory hyperpigmentation, or darkening of the affected skin, can also occur from this trauma," she says.