Brief Answer:
As discussed in details below.

Detailed Answer:
Hi.
Thanks for your query.
To recapitulate: Female/55 - wants to know what to do for itchy top of a butt crack...
Please provide additional information:
Since when is this problem?
Any medical problems like diabetes or so?
I hope, there is no swelling.

If there is itching at the top of the butt crack, the commonest problem is dermatitis of the inter-gluteal furrow region.

The exact cause of this condition is not known, but this is treatable and can be cured.
It usually starts as a itch, particularly n summer season. This is probable due to inability to clean up this area nicely with water, retention of the sweat, soap and so on.
The itching causes small injuries and mild infection. The area may weep, gives fluidly secretion and causes more itching , particularly at night.
Patients starts using whatever ointments are available or suggested by friends, family or local Doctors. Feels good, but the disease remains there to recur or have vexing and vanning.
Many patients have some or the other problems with digestion or motion.

I do advise all such patients as follows::
-Clean the area with plain water as frequently as possible.
-Apply liquid Povidone Iodine locally to the whole area and allow it to dry.
No other ointments or lotions/ soaps / chemicals are needed.
-A small course of an antibiotic and Metronidazole for about 5 days ( you need a prescription please- of a local Doctor) only if there is an infection.
-This is basically a disorder due to deficiency of vitamins and minerals that the integrity of the skin is lost. So you have to have therapeutic dosage of Vitamin A and D and to continue as multivitamins which are available as anti-oxidant medicines for about a month or so.

Check for blood sugar.
Check for any Pilonidal sinus or cyst.

I hope this answer helps you.
Please feel free to ask for further relevant queries if you feel that there is a gap of communication.

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