Swelling and pain in the big toe is usually due to a secondary bacterial infection caused by cracking of the keratinized skin on the toe, or other causes. The infecting bacteria is usually Staphylococcus aureus, which causes abscesses between the toes or nail fungus. Early clinical manifestations are localized redness, swelling, heat, and pain, which usually require prompt treatment with oral or even intravenous antibiotics, the first choice of antibiotic treatment being penicillin or a generation of cephalosporin antibiotics. If it develops further, it may form an abscess between the toes or purulent toe infection, which may repeatedly persist and may even form a nail infection and require nail removal. If purulent toenitis develops, it usually requires prompt incision and drainage, along with oral antibiotics and even intravenous antibiotics.