Brief Answer:
Please see detailed answer

Detailed Answer:
Hello! Thanks for putting your query in HCM. I am a Gastroenterologist (DM).
Black specks in stool may be due to bleed from gastrointestinal tract or may be due to diet you have taken. Among the diet like banana, apple, carrot, iron supplements, aspirin intake etc. This is quite common and usually, there is no course for alarm.So I will advise you to eliminate the food items and medication if any rich in iron, if still there are black specks then you should consult your doctor who will evaluate you. An itching in ass may be due to Pagets disease, crohns disease, infection, diet induced, dermatitis, leakage of stool or mucus, rectal prolapse, diabetes mellitus, candidiasis. So I will advise you to visit a Gastroenterologist and Dermatologist. They may take a detail history and may advise for colonoscopy, skin biopsy, some blood tests. However many a times there are no cause for it. Meanwhile what you should do which I found very useful in my patients are:
1.Avoid coffee, cola, or chocolates, dairy products,citrus fruits, beer.
2.modify your cleansing habits that is stop polishing (rubbing while cleaning) anus
3.Wipe it gently with wet facial tissue or baby wipes
4.Avoiding soap and a washcloth in the shower and use plain water and hand to wash the perineum in the tub or shower.
5.Creams or emulsifying ointments may be used instead of soap.
6.Perfumed soaps and astringents (such as witch hazel) should be avoided. 7.Tissue paper or a cotton ball placed by the anus and changed several times a day will absorb moisture and create a drier environment.
8. A diet high in fiber with plenty of fluids
9.A limited amount of 1% hydrocortisone cream can be used.
10.Intradermal injection of methylene blue should be used as last resort
11. Take one tablet of Albendazole and repeat it after 14 days
I hope I have answered your query and this will help you. If you have any further query I will be happy to answer that too. Remain in touch and get-well soon.

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