First forecox is a combination of 4 antibiotics used purposely for treatment of tuberculosis
. If you are actually having an anal fistula
, i'll suggest you book an appointment with a surgeon for surgical intervention. Antibiotics such as cloxacillin/oxacillin/ amoxicillin-clavulinic acid would have equally been effective.
What needed to be done is determining the depth of the fistula so that the type of surgical procedure could be indicated.
In my humble opinion, you will need to stop forecox except that you are having an associated tuberculosis infection that the doctor was aiming to treat.
Wish you the best