Do ask your doctor either for Diltiazem or Nifedipine ointment or nitro. These are what can help a fissure. Hydrocortisone only thins the skin and does nothing for a fissure.
There is a lot of information to be had on here under the section where you have posted. Usual things are: use Miralax, make sure you do not overdo the fibre, use a Sitz Bath to soak, drink enough water and see a colon and rectal surgeon if you have not done so already.
Also, we have a great search above, between FAQ and Portal above. There you can search by topic as well as message text.
And

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