Is It Safe To Take Vermox Tablets During Menstrual Cycle?

i m 26 female ,i have doubt that m having worms in my intestine due to anorexia,underweight problems.wanna ask that is it save to take vermox(anti helmentic) 500 mg tablet during menstrual cycle..as i use to face dismennorhea these days and also have history of chronic constipation.Also tell me what is the suitable time to take anti helmentic drugs for maximum effect.