My Neurologist told me about Vitamin B2 research showing promise. Take 200 mg in am and 200 mg in pm. It worked I went from a pain level 10 to a 4 and now after my surgery I only get a headache when I haven’t gotten enough sleep. I continue to take as you cannot overdose on B2 your body will urinate out what you don’t use. Your urine will be yellow. Remember to take as above as taking 400 mg together doesn’t last all day and you will only urinate out what you are not using.

I found this Riboflavin - Health Professional Fact Sheet.

This article mentions some risks https://www.mountsinai.org/health-library/supplement/vitamin-b2-riboflavin

As always make sure you check with your PCP and let them know all the OTCs you take!