It seems u had a Perianal abscess previously and it led to formation of fistula . But any drugs u take it only heave a temporary solution . It only controls infection and temporarily closes fistula tract but again it will recur. So consult a surgeon and if possible get an ultrasound or MRI fistulogram done and based on the report plan accordingly .
Next Steps
Consult a surgeon or get an MRI fistulogram
Health Tips
High fibre diet , Sitz bath , avoid spicy and non veg food for few weeks