Acne

Basic lesion is a comedome – papules that are open (black head-due to melanin) or closed (white head) and can be inflamed (pustules, nodules, cysts)
Usually linked to changes in hormones during puberty but can be caused by medications including steroids, anticonvulsants, POP, and hyperandrogenism
Differentials – rosacea, periorofacial dermatitis (sides of eyes,mouth) – no comedomes present, skin tends to be dry not greasy
Mild, moderate, severe including nodulocystic, acne fulminans (systemic unwell)

General skin care
Resist picking or scrathing as can cause scarring
Sunscrean – UV radiation can aggravate acne
Non alkaline skin cleanser

Benzoyl Peroxide – potential for bleaching, photosensitivity, irritation (BPI side effects)
Start short duration then build up

Benzoyl Peroxide + Clindamycin – for mild acne

Benzoyl Peroxide + Adapalene (Epiduo)

Tretinoin + Clindamycin
– topical retinoids contraindicated in pregnancy

Oral antibiotics
Use in combination with topical treatment (but not with topical antibiotic) such as azelaic acid, epiduo
Doxycylcine 100mg daily
Trimethoprim
Erythromycin
Stop after 3 months if acne resolved (to reduce resistance), or if partial improvement continue further 3 months. Stop at 6 months. Can repeat course if recurs.

Combined oral contraceptive pill
– all types effective but 3rd/4th generation such as mercilon, yasmin, lucette preferrable (slightly higher DVT risk)
– Dianette (co-cyprindiol) higher DVT risk so only used in PCOS-related acne

Oral isotretinoin (Roaccutane). British Association of Dermatologist PIL. https://www.bad.org.uk/pils/isotretinoin/
– risk of depression, suicidal thoughts… but treating acne can improve mental health
– low libido, vaginal dryness, erectile dysfunction
– powerful teratogen – need 1 very reliable contraceptive or 2 effective methods (eg. COCP and condom)