Pimples or acne is an inflammatory skin disorder. The main reason behind the pimple/acne problem is the hormonal changes that take place during puberty/adolescence. Teens generally produce more sebum than adults, resulting in an increased incidence of acne. The extra outflow of sebum damage the cells lining the sebum canals within the skin follicles and plug the skin pores. This ultimately result in pimple/acne formation.