I have itching between my big toe and it has been going on for three days now. what could be the cause there is no swelling or blister?

Tinea pedis: You may be describing tinea pedis or athlete's foot. Check out http://www.Mayoclinic.Com/health/athletes-foot/ds00317. There are otc medications available w/o prescription at most drug stores. Most important is to keep feet dry & be sure to wear flip flops if you shower in public areas eg gym locker rooms.

Probably: Probably from sweating overgrowth of bacteria in the area. This causing histamine release.

Skin irritation: This could be due to the starting fungus skin infection, athletes foot. If it is only related to the web space next to the big toe, it could be due to wearing the flip-flops. A physician may need to look at it closely, as a topical medication is often rxd for this problem.

Athletes foot : Is most likely cause. There does not have i be anything visible the. Try antifungal cream. If you had been wearing a flip flip with a thong then the thong piece could of irritated throu friction, in which case discontinue wearing it.