At what age do people normally begin to have trouble with acne?

Early Teens. Early teenage years is when acne typically appears and is a rite of passage for so many young adolescents. Fortunately most cases are transient and can be handled with good skin hygiene. Areas of the face with more oily glands (sebaceous skin) , known as the t-zone. Across the brows and then right down the nose to the mouth represents the areas of most trouble.
Age 12-14 years. People begin to have some acne problems as they enter puberty, because that is when hormonal changes happen.