I dealt with the same surprise in my early thirties after having clear skin for years. When I consulted with an acne treatment dermatologist, they explained that adult cases often require a more nuanced approach. They looked at potential hormonal factors, my lifestyle, stress levels, and even my skincare routine. The treatment plan they developed was specifically designed for adult skin - effective for clearing breakouts but also incorporating ingredients that supported overall skin health. It's definitely not the same as treating teenage skin, so finding someone who understands adult cases specifically is important.