Hello,
Brown patches on the skin commonly are indicative of notalgia paresthetica. Other medical conditions that may cause such symptoms are hormonal disorder (Addison's disease), side effects of oral contraceptives, exposure to excessive sunlight or toxic chemicals or genetic disorder.
You are suggested to avoid excessive exposure to sunlight. Stay away from pollutants when outdoors, be careful of what type of
contraception you use & for what period of time. Get clinically examined by a GP/
Dermatologist, get hormonal tests done. Get X- ray, CT, MRI done to rule out Addison's disease and detect Notalgia Paresthetica.
Your treatment (by antibiotics or Ultraviolet B (UVB)
light therapy will depend on the pathology and severity of the disease detected. In the meantime you can apply
Capsaicin cream or corticosteroid
ointments locally. Do not scratch. Take care of your hygiene.
Take care. Hope I have answered your question. Let me know if I can assist you further.
Regards,
Dr. Nupur K., General & Family Physician