Brief Answer:
you need specific medications & self care.

Detailed Answer:
Hi llovefunyuns,
Thanks for the query under HCM.
* Anal itching is a intolerably disturbing problem, The uncontrolled itching, leads to burning & pain in the area. In your case it has lead to a chopped like raw area, with patchy look.. the white patches in between are mostly due to the infection causing itching.
* To manage the condition it's needful to find the cause for the anal itching. Though there are many causes for anal itching like-- Simple sweating, diarrhea, hemorrhoids, worm infestations, diabetes . But the the appearance of the lesion ( whitish & chopped skin), indicates it to be mostly,Yeast infection or candidosis with secondary infection. Very remote possibility of psoriasis remains ,
* Investigations like - blood sugar/ culture of swab taken from the lesion/ stool examination apart from detailed local examination by an expert skin specialist will help for pin pointing the cause.
An appointment with skin specialist should be fixed.. by the time you can meet one, you can.start with....
* Self care-
- Clean anal area with plenty of plain water after motion/ tap it dry & apply Metranidazole skin ointment avialable over counter .
- tAKE STOOL SOFTNER & avoid constipation,
- avoid chillies/spicy diet. drink plenty water,
-Do not itch/rub the part,
- yeast infection can spread through sex.. avoid sex,
* In this context I would advise you to consult tour family physician first. He would examine you & will start with treatment/ refer you to skin specialist/ anal surgeon for expert advise as per need.
* Treatment given will depend on the cause found.
- local hygiene with specific ointment,/ restrain itching.
- anti fungal/ antibiotic /anti allergic / anti inflammatory medicines orally. In yeast infection treatment of both sex partners is given.
- Medicines to control diabetes , if needful with dietary advise.
- anti worm dose will be given as per need.
Thus, with proper local care of the lesion/ specific medicines & expert's advise as per need would help you to get rid of the problem in few days time.
* Still it remains important to be careful about genital/anal hygiene for such infections are notorious to recur.

I hope the answer is both informative & useful to you. Any follow up query is welcome.
Thanks.

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