Anal fissure or a tear in anal mucosa results from passage of hard stools. To be relieved of symptoms make sure the stools are soft.
That means you need to take osmotic laxatives like lactulose...lacitatol or PEG preparations.
Next Steps
First step is called chemical sphincterotomy wherein one applys chemical agents into the anus by inder figer. Commonly used agents are diltizem and nifedipine. Apply thrice daily for one month even if you are relieved of pain.
Health Tips
Applying ointment outside anus is useless.
If you have recurrent fissures then Surgery is an option. Lateral internal sphincterotomy gives excellent results.