Constant anal itching, especially after scabies and with an anal fissure, can be incredibly distressing. Since antihistamines like Atarax and Xyzal aren't helping, and lignocaine only provides temporary relief, the skin may be highly sensitized or experiencing post-scabies irritation. It is also possible a secondary fungal infection has developed from excess moisture. Please avoid scrubbing the area or using harsh soaps. I gently recommend seeing a doctor or dermatologist. They can evaluate if the fissure is healed and safely prescribe a targeted mild corticosteroid or antifungal cream to finally give you lasting relief.