Skin Disorders, Diseases, and Contraindications
Recognize, do not diagnose
An esthetician describes and refers; only a physician diagnoses. Learn lesion vocabulary: primary lesions arise first (macule, papule, pustule, vesicle, bulla, wheal, nodule, cyst) and secondary lesions evolve from them (scale, crust, excoriation, fissure, ulcer, scar, keloid). Being able to name what you see keeps your notes professional and your scope intact.
Categories you must sort quickly
Pigmentary: melasma, vitiligo, post-inflammatory hyperpigmentation, solar lentigo, nevi. Inflammatory: acne (grades 1–4), rosacea, seborrheic dermatitis, atopic dermatitis/eczema, psoriasis. Infectious: herpes simplex (cold sore), conjunctivitis, impetigo, tinea, verruca/warts, scabies, pediculosis. Malignant: basal cell carcinoma, squamous cell carcinoma, melanoma - remember ABCDE (asymmetry, border, color, diameter, evolving).
Contraindications that end the service
Active infection, undiagnosed lesions, open or broken skin, severe inflammation, recent surgery, sunburn, and allergy to a product all stop the treatment. Isotretinoin typically requires a six-month wait before waxing or peels; photosensitizing medications, pregnancy, pacemakers, and recent chemical peels change what is safe. Refer any client with cystic or conglobate acne, suspicious growths, or a rash you cannot identify.
Rule of thumb: if you would not touch it on your own face, do not touch it on a client's - refer and document.