Hello,
You need to send proper photographs of your lesions and detailed history of thosr patches like how did it started? Family history? Onset of lesion and duration? How it started ? Any other symptoms? Everything ? Whether its hypopigmented or depigmented??
White patches have lot of differential diagnosis so need to rule out specific cause
Next Steps
I would suggest you better to yout doctor who prescribed you neosoralen because he/she might be knowing your cause better that's why it has been prescribed to you
Otherwise its completely safe if given for proper cause like if it is mainly for vitiligo
Health Tips
As this medication increases photosensitivity, I would just suggest you to use a sunscreen with good SPF and to avoid unnecessary prolonged sun exposure
This medication will take time and you have to take for longer period
For more details, consult me through practo pro