What Causes Itchy Scalp And Discolored Skin Patches After Using Hair Color?
Possible fungal infection
Detailed Answer:
Hello,
Thank you for using HCM,
From what you are describing looks like it may be a fungal infection of the scalp called tinea capitis.
The diagnoses is decided by the looks of it, so if you can provide a photo, I may confirm it for sure. I'm pretty confident though that it is that, because there are not problems that I'm aware of with that description.
If that is the diagnoses, and if I was your caring doctor, the recommendations of treatment for that kind of infection are taking an antifungal by mouth. The most effective drug is terbinafine (Lamisil Oral Granules) 250 mg/day for 6 weeks.
Those drugs have side effects and are quite expensive, so I would recommend to double check my suggestion with a local dermatologist, and make together a plan.
As per your question if it is caused by ammonia or peroxide, I don't think it is. In general its caused by fungus, that grows on the skin sometimes due to factors that allow it to grow, and sometimes just happens.
Hope this is helpful.
Please feel free to ask if you have further questions.
Take care,
Dr. Papaqako