Collagen can be supplemented during menstruation. For women, collagen can improve the symptoms of sagging skin, can make the skin elastic and shiny, and can make the skin delicate, so it will have a beauty effect. If you take collagen during your menstrual period, it will not cause any changes to the amount of menstruation, the color of menstruation or the duration of menstruation, so you can take collagen without worry. If you have a protein allergy, you must be cautious, because once the allergic reaction to the body will cause a great impact, so after the allergic reaction to stop using collagen, you can change to other methods to improve the skin condition, give the corresponding beauty, you can go to the beauty salon, or use other topical drugs or masks to improve.