anodynia

an- +‎ -odynia.

anodynia (uncountable)

1. (medicine) The absence of pain in a previously painful region.

• analgesia
• analgia
• antalgesia

• anodyne

ano- +‎ -dynia

anodynia (uncountable)

1. (medicine) Anal pain; anorectal pain.
   • 2013, Tomasz F. Mroczkowski; Larry E. Millikan; Lawrence Charles Parish, Genital and Perianal Diseases: A Color Handbook, page 260:

     Anodynia (anorectal pain) most frequently occurs together with other pain syndromes, like vulvodynia or phallodynia, but sometimes it may be isolated.

• proctalgia

• analgia (which seems like it might mean "anal pain" (ano- +‎ -algia) but which actually means "no pain" (an- +‎ -algia))