It seems that your girl friend may be having phytophotodermatitis
It may be due to contact with some plant and exposure to sun.
There is erythema
with bullae in linear form.
There may be burning and itching.
Tell your girlfriend to avoid sunexposure.
Tell to apply some antibiotic cream like sisomycine cream.
Give her antibiotics and anti inflammatory drugs.
If needed, give her steroids in tappering dose.
If there is itching ,give her antihistaminics like levocetirizine
She will feel better.
However,she should consult dermatologist
I hope you got my answer.
Dr. Ilyas Patel MD