Why pimples happen
During puberty, hormones make the oil glands in your skin more active. Oil and dead skin cells can block tiny openings called pores.
Blocked pores can become blackheads, whiteheads or red, swollen pimples when bacteria and inflammation join in.
Most teenagers get some acne. It is not caused by being dirty, and it is not your fault.
Gentle everyday care
Wash your face twice a day and after sweating with lukewarm water and a mild cleanser. Scrubbing hard can make acne worse.
Choose products labelled non-comedogenic or oil-free, including sunscreen and moisturiser.
Keep hair clean, wash pillow covers often, and try not to rest your face on your hands or phone.
Hands off
Picking, squeezing or popping pimples pushes germs deeper and can leave dark marks or scars.
Dark marks after pimples are common on brown skin. They fade slowly over months, and sunscreen helps them fade.
When to see a doctor
If acne is painful, leaves scars, does not improve with gentle care, or makes you feel bad about yourself, see a doctor. A skin doctor is called a dermatologist.
Doctors have effective treatments. Do not use creams from a chemist, salon or online without a doctor's advice, especially creams with steroids, which can damage skin.