·	picking and squeezing the spots may cause further inflammation and scarring1

·	stress can make acne worse in some people, although it is not clear why1,5

·	in women, outbreaks may be affected by the hormonal changes that occur during the menstrual cycle1,5

·	excessive production of male hormones such as testosterone from conditions such as polycystic ovary syndrome may be another cause.5 For more information, please see the separate BUPA factsheet Polycystic ovary syndrome

·	some contraceptive pills may make acne worse. This is due to the type of progestogen hormone in some pills whereas some other types of contraceptive pills can improve acne - see Treatments section below. Your GP will advise you which contraceptive pill to take1,5

·	some medicines can make acne worse. For example, some medicines taken for epilepsy, and steroid creams and ointments that are used for eczema. Do not stop a prescribed medicine if you suspect it is making your acne worse, but tell your GP. An alternative may be an option

·	steroids can cause acne as a side-effect