marks on buttocks

Thanks for your question! I am sorry to hear that you are experiencing unpleasant scarring from your carbuncle infection. According to WebMD, scarring is a natural part of the healing process after injuries. Many factors, such as depth and size of the wound, location of the injury, age, sex, and heredity can all affect the scarring process and how your skin reacts.

Possible treatments may include over the counter or prescription creams, gels or ointments; surgical removal or treatments; or certain injections (such as steroids for protruding scars). The least invasive and least expensive option is the over the counter or prescription creams, gels, or ointments. Scar Cream Resource provides a list of recommended scar creams and active ingredients. Some recommendations include:
-Syprex Scar Cream
-Cica Care
-Biodermis
-Mederma
There are many more options listed at: http://scarcream.org/

Many times, how you treat the infection during the healing process greatly affects the end-result of scar formation. Carbuncles (or boils) should be washed with a warm compress 2-3 times each day and covered with medicated ointment and a bandage. This generally helps to prevent further infection and limit scarring.

To help prevent boils from occurring it is recommended to:
-carefully wash clothes, bed linen, and towels (especially during and after healing of current infection)
-clean and treat minor skin wounds
-practice good personal hygiene

More information can be found on: http://www.webmd.com/skin-problems-and-treatments/boils

Hope this helps!