Anal or perianal itching is a common skin condition that goes undiagnosed and untreated for years, because patients are embarrassed to bring that up to their doctors. Many patients think, ”They have to look down there? No way!” The importance of bringing this “embarrassing” topic up with your doctor cannot be overestimated.
Anal itch (pruritus ani) has a number of causes. The right diagnosis has to be made first. Then treatment depends on the diagnosis.
Possible causes of anal itching (1):
Fecal contamination due to either soiling (overt or occult) or inadequate cleansing. Approximately 50% of patients with pruritus ani have loose stools. Just to add (see below), hemorrhoids, growths (benign or malignant) at the anal opening or above it may increase soiling, again pointing to the need for a checkup.
Trauma from overzealous wiping or cleansing
Perianal infection with bacterial or fungal organisms. Fungal organisms, dermatophytes (those that cause athlete’s foot, ringworm and jock itch) and yeast (Candida) account for approximately 15% of pruritus ani.
Allergic contact or irritant dermatitis, which can be caused by creams, soaps, wipes, topical medications, scent in toilet paper or laundry products, etc.
Certain foods. This one has not been completely worked out, but citrus, tomatoes, caffeine and anything that promotes loose stools can potentially contribute to itching.
Dermatologic conditions, like eczema, psoriasis, lichen sclerosus.
Tumors, such as anal or colorectal cancer, perianal Paget’s disease (usually an extension of adenocarcinoma from the rectum), and Bowen’s disease (squamous cell carcinoma). HPV infections of the area may lead to development of squamous cell carcinoma in the area as well.
Use of topical steroids, which leads to thinning and hypersensitivity of the perianal skin.
Stress or anxiety have been implicated as well.
Here is the biggest problem. Once the perianal skin is scratched or rubbed, it becomes much more itchy, which leads to more scratching, creating a vicious cycle. The skin thickens, darkens and has accompanying neural changes leading to a condition known as lichen simplex chronicus. (2)
So treatment of anal itching very much depends on the cause. A proper diagnosis must be made first. However, even when the cause is found and eliminated or corrected, the problem is how to deal with the itch.
Aside from prescribing medications to treat the skin condition, here is what I recommend for my patients with anal itching:
Eliminate chlorine and all dyes and fragrances in anything that may touch the skin, including laundry detergents, fabric softeners, perfumes, etc.
Switch to a non-soap cleanser. One of my favorites is Cetaphil cleansing bar (not the antibacterial one)
Stop using washcloths, sponges, anything that rubs the skin in any way.
After a bowel movement, wet a toilet tissue with warm water, wipe with the wet toilet tissue and then blot (not rub) the area with the dry one.
Eliminate any wipes that may be used for cleansing. They are easy to use but can irritate the skin.
When drying yourself after bathing, blot the area with the towel.
The perianal area is exquisitely sensitive to itch. The first thing in successful treatment of perianal itching is breaking the itch-scratch cycle. Even after successful treatment of perianal lichen simplex chronicus, the area is still very much prone to itching, so one should be very conscious of any rubbing or scratching as the condition will recur quickly.
Siddiq et al. Pruritus ani Ann R Coll Surg Engl 2008;90:457-463 http://www.ncbi.nlm.nih.gov/pmc/…
Hogan DJ Lichen Simplex Chronicus. Medscape Reference http://emedicine.medscape.com/ar…