Views on buying light treatment for home use

Hi My daughter is 9 and has had plaque psoriasis for 6 years which has been kept at bay with topical treatments. She developed Guttate psoriasis 7 weeks ago and her skin and scalp have exploded. I've sought GP referral back to hospital to try and eradicate it as much as possible as she is being teased at school and refuses to go. She also suffers with anxiety so not a good combination to have. I was wondering about purchasing a light treatment unit for home use. What are peoples views? Or do you have any herbal remedies that might work. Thanks