i will need to know more info. is there an opening near the infection site? If there is an open wound, you will need x-rays and possibly an MRI to rule out bone infection, which can make an infection linger for long periods of time.
do you have swelling in the legs also?
you could have venous stasis that can turn into lymphangitis (infection of the leg with redness going up the leg)--for this treatment, you would need compression to reduce the swelling and IV antibiotics.
Where is the infection coming from? Ulcer? Ingrown toenail?
What kind of treatment have you received so far?