Brief Answer:
Try warm sitz bath...

Detailed Answer:
Hi,

Besides the pain medication, I suggest the following:
1. Warm sitz bath three or four times a day. It is the most effective pain relief measure in most patients with similar problems.
2. Start stool softening measures. Drinking plenty of fluids; plenty of fruits and vegetables; and or using a stool softener such as Syp lactulose at night is necessary.
3. Topical pain reducing agents. Some topical agents - steroidal and non steroidal hemorrhoid creams can be used.

Finally it is important to see a doctor for per rectal examination. Commonly per anal pain is caused by fissures which are usually self resolving. If it is indeed fistula, I think you also need an antibiotic drugs. Healing of fistula needs to be monitored by follow ups. Therefore it is worthwhile to see a doctor.

Hope this helps. Let me know if you need clarifications.

Regards

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