Hi! So I take lysine tables (at least 1500 mg/day) when I get a cold sore, because the amino acids in lysine help fight off the virus. I've taken lysine the last two days, because I started getting a cold sore yesterday. I started my period about 2.5 days ago. The first day seemed pretty normal, but since then, my period has been pretty light compared to usual, and my stomach has been a little grumbly/upset. So I'm wondering if the lysine tablets can have an effect on menstraul blood flow and if so, can it kick in this quickly? I believe I took 1500 mg of lysine last night and at least 1500 mg today. Could this amount of lysine explain why my stomach is upset or why my period is lighter? I've never taken lysine while on my period before. Any help would be greatly appreciated! Thanks!