A persistent need to scratch your bottom may be something that is too embarrassing to ask about, but there is good information about this very common anal symptom. Doctors are certainly not embarrassed about discussing the problem with patients, and it can be treated successfully.
Contents of this article:
You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.
Fast facts on anal itching
Here are some key points about pruritus ani. More detail and supporting information is in the main article.
- Anal itching may be embarrassing - but it is a common problem seen by doctors.
- Most causes are secondary - there is something underlying the itching symptom.
- Too much or too little cleansing can lead to itchiness around the anus.
- Some foods and drinks are associated with pruritus ani.
- Skin conditions, infections, anorectal disorders, whole-body medical conditions, and drugs are all potential causes.
- Diagnosis starts with a number of questions, and will involve a physical examination, probably including a digital rectal examination by the doctor.
- A number of practical measures may be successful in preventing and treating an itchy bottom.
- Drug treatments prescribed by a doctor may offer relief in appropriate cases.
What is pruritus ani?
Pruritus ani is a medical way of saying itchy bottom. Other terms include:
- Anal pruritus
- Perianal itching
- Anorectal itching
- Itchy butt/bum/bottom.
The anus is the orifice or opening at the end of the gut or digestive system, allowing us to expel solid waste from the body. Pruritus ani refers to itching around the anus.
Anal itching is a symptom - not itself the diagnosis of a condition.1
What causes anal itching?
Scratching an itchy bottom can make the problem worse.
Pruritus ani can have a primary or secondary cause. Primary causes - that is, essential conditions that are not the result of something else underlying them - are either functional or psychological.
In functional anal itching, a small amount of feces escapes because of anorectal dysfunction, directly causing the itching.1
In psychological anal itching there is no physical problem with the anus or the skin around it. This mind-related problem can be complex, associated with psychosomatic or psychiatric disorders (depression, for example).1
The list of secondary causes of anal itching - those in which there is an underlying cause - is much longer. These may be collected into broad groups:1-4
- Hygiene (too much or too little), and skin irritants (such as soaps)
- Skin (dermatological) conditions (such as dermatitis and psoriasis)
- Anal or rectal disorders (piles, and anal fistulas and fissures, for example), which may lead to fecal soilage
- Infections (including parasitic and sexually transmitted)
- Systemic (entire body) medical conditions (including aplastic anemia, diabetes, inflammatory bowel disease, jaundice, leukemia, lymphoma, thyroid disease)
- Foods (dietary irritants, such as chilli peppers)
- Drugs - chemotherapy, colchicine, neomycin, quinidine.
Some foods may be making the problem worse, so identifying and avoiding these may help. Examples include:5
- Spicy foods
- Citrus fruits, such as oranges
- Dairy products
- Excessive liquids, such as milk, beer or wine.
Often, no cause is identified for the itching - in these instances, the pruritus is labelled idiopathic.3,6,7
Diagnosis of anal itching
The first time someone presents the problem of anal itching to their doctor, the consultation would start with a number of questions in the process of 'taking a history'.
The doctor may take the following lines of enquiry:1,2
- Ask about the duration and pattern of the itch
- Explore dietary intake, and hygiene practices to see if there may be excessive washing, or use of creams, perfumes, or soaps
- Evaluate how severe the itch is, and work out its impact on life.
Other information will help to pin down a possible cause for the pruritus ani:1,2
- Is there a relevant past medical history, such as anorectal surgery, hemorrhoids, or diabetes?
- Has there been any urinary or fecal incontinence?
- Is there blood on toilet paper, anal pain or lumps to indicate hemorrhoids?
- Has there been any bloody diarrhea and abdominal cramps (suggesting inflammatory bowel disease)?
A physical examination may follow, so that the doctor can see how the problem looks, checking for signs of skin cracking or inflammation and any bleeding around the anal area.1,2
A visual check may also reveal hemorrhoids, anal fissure, or eczema, for example. It may simply reveal soiling as the issue.
An internal examination is also performed by the doctor - by inserting a gloved and lubricated finger through the anus into the rectum.1,2,5
This is known as a digital rectal examination. This internal examination helps to diagnose hemorrhoids or constipation as well as help to rule out suspected cases of bowel cancer, which are rare.1,2,5
The doctor may ask you to clench your bottom, as a test of the anal sphincter, or ask you to push, as a way of looking for internal hemorrhoids that get pushed through to the outside (prolapse).
Treatment and prevention of anal itching
Here are some practical tips to help with the treatment and prevention of an itchy bottom:3,5,6,8
- Avoid highly seasoned and spiced foods, and maintain a regular bowel habit
- Keep the anal area clean after emptying the bowel
- Avoid medicated, perfumed or deodorant soaps - use only plain warm water for cleaning, or aqueous cream or emollients
- Use moist toilet tissues instead of paper
- Avoid allowing the anal area to stay moist, and dry it gently by dabbing, not by rubbing
- Use drying powders, but not medicated or scented ones
- Avoid scratching the area, which creates further trauma and makes the problem worse
- Wearing socks or cotton gloves on the hands may reduce the harm from subconscious scratching for people who find they have been unable to resist overnight scratching
- Wear loose, breathable clothing, avoiding materials such as acrylic and nylon, which trap sweat.
Doctors helping with the treatment of anal itching will be able to treat any secondary or underlying causes for the problem, from hemorrhoids to skin problems.6
An infection with Candida (also known as thrush), for example, may be treated with antifungal drugs. Another example is small skin tags that may hide fecal residue or trap moisture - if this is the secondary cause, practical measures to ensure hygiene may be taken.3
The list of practical tips given above may also be offered in the consultation, perhaps in the form of an information leaflet.3
The doctor may help with a process of elimination, systematically removing potential irritants to see if that helps.3
If itching is particularly troublesome during the night, doctors may offer an antihistamine such as hydroxyzine (Vistaril).4
A soothing ointment - bismuth subgallate or zinc oxide, for example - are prescribed for some skin problems.1
Inflammation of the perianal skin may receive short-term topical drug treatment in the form of a mild corticosteroid - hydrocortisone, for example.3 However, some research has shown that, as an initial treatment step, cleansing can be as effective as corticosteroid.3,7
The hydrocortisone is prescribed at the 1% formulation.2,3 More potent steroids may be used in more severe cases.2
Recent development about anal itching
Pruritus may have a comparable effect to pain on quality of life. This medical research published in 2011 found that chronic itching can be as serious as chronic pain in terms of effect on quality of life.
Written by Markus MacGill