Author Affiliations: College of Medicine (Mr Gardner) and Department of Dermatology (Drs Davis and Pittelkow and Ms Richardson), Mayo Clinic, Rochester, Minnesota. Mr Gardner is a visiting medical student.
Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), a common preservative in some brands of moist toilet paper (baby wipes and moist towelettes), has been reported to be a cause of allergic contact dermatitis. However, few cases have been reported in the United States.
We report the cases of 4 adult patients with severe perianal and perineal allergic contact dermatitis seen at our institution during a 6-month period. With patch testing, we identified allergy to MCI/MI, and we determined that all 4 patients were using moist toilet paper. The dermatitis resolved after use of the moist toilet paper was discontinued.
This study highlights that the MCI/MI in moist toilet paper can be a cause of perianal and perineal allergic contact dermatitis.
The use of moist toilet paper (baby wipes and moist towelettes) to cleanse after defecation is a relatively recent regular practice among many adults. Methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), a common preservative in cosmetic and industrial products, is a well-known allergen and is an ingredient in many brands of moist toilet paper. Perianal and perineal allergic contact dermatitis (ACD) due to MCI/MI-containing moist toilet paper has been reported from Europe, but few reports have come from the United States. Herein, we report the cases of 4 adults with severe perianal and perineal ACD from using moist toilet paper containing MCI/MI for their intimate personal hygiene who were seen in our Department of Dermatology between January and June 2009. We present these cases to raise awareness among health care providers of the possible hazards of MCI/MI-containing moist toilet paper.
A 49-year-old man who was a mail carrier sought medical care for a perianal and intragluteal eruption with associated pruritus and pain of 5 months' duration. He judged the pain to be of the highest intensity, 10 on a scale of 1 to 10, and had not worked for the previous 2 months because walking was so painful. The eruption was recalcitrant to topical corticosteroids and had not responded to nystatin cream, trypsin complex ointment, or fluconazole. He had seen numerous physicians before coming to our dermatology department. Physical examination showed bright red confluent patches in the perianal area extending onto the right buttock, discrete and confluent papules on the left buttock with fissuring (Figure 1), and pink patches on the face and arms. Biopsy specimens of the perianal area showed subacute dermatitis, and patch testing to a standard series demonstrated a positive allergic patch test reaction to MCI/MI (Table 1). On close questioning after the patch testing, the patient disclosed that he had started to use Cottonelle (Kimberly-Clark Corporation, Neenah, Wisconsin) moist toilet paper before the onset of this skin eruption. Because Cottonelle moist toilet paper contains MCI/MI, the patient was advised to discontinue the use of the moist toilet paper and to avoid future use of products containing MCI/MI. Six months later, the patient reported an 85% to 90% improvement after switching to a different moist toilet paper that did not contain MCI/MI and using topical corticosteroid treatment.
Case 1. Bright red confluent patches in the perianal area extending onto the right and left buttocks in a 49-year-old man who used moist toilet paper.
A 63-year-old woman sought care for severe pruritus and irritation of the genital and perianal areas of more than 1 year's duration. The patient had seen numerous physicians and was given a diagnosis of pityriasis rubra pilaris, for which she received methotrexate treatment, with subsequent development of hepatotoxic effects. Furthermore, she had tried topical and oral corticosteroids. Physical examination showed confluent erythematous patches bilaterally on the labia majora and mons pubis extending to the perianal area (Figure 2). Patch testing to a standard series demonstrated a positive allergic reaction to MCI/MI (Table 1). The patient disclosed that she regularly used Cottonelle moist toilet paper for intimate personal hygiene. Six weeks after beginning topical corticosteroid treatment and discontinuing use of the Cottonelle wipes, the patient reported a 95% improvement.
Case 2. Erythematous patches bilaterally on the labia majora and the mons pubis in a 63-year-old woman who used moist toilet paper.
A 70-year-old man with a history of psoriasis came to our dermatology department with severe pruritus in the perianal area of 20 years' duration. The patient had seen numerous physicians in the past, and the perianal lesions were thought to be involvement by psoriasis, but they were recalcitrant to treatments such as clobetasol propionate, Epsom salts, and zinc oxide. Physical examination revealed pronounced perianal erythema, some acanthosis, and a fissure of the perineum at approximately the 5-o’clock position (Figure 3A). The patient reported using Cottonelle moist wipes. Patch testing to a standard series demonstrated a positive allergic reaction to MCI/MI (Figure 3B and Table 1). Two weeks after beginning triamcinolone treatment and discontinuing use of the Cottonelle wipes, the patient reported an 80% to 90% improvement. At 6 weeks, the patient reported a 99.9% improvement and was using a non-MCI/MI wipe at last follow-up.
Case 3. A, Pronounced perianal erythema, some acanthosis, and a fissure of the perineum in a 70-year-old man who used moist toilet paper. B, Patch test result demonstrating a positive reaction to the allergen methylchloroisothiazolinone/methylisothiazolinone.
A 38-year-old woman sought care for severe perineal and perianal dermatitis with fissures of 1 year's duration. The patient had seen numerous physicians and tried treatments including clobetasol, desonide, oral antibiotics, and antifungal agents. Physical examination revealed mild erythema and white papules in the perineal area (Figure 4). Patch testing to a gynecologic and standard series demonstrated a positive allergic patch test reaction to MCI/MI (Table 1). The patient reported using moist toilet paper of an unknown brand. One month after beginning topical corticosteroid treatment and discontinuing use of the moist toilet paper, she reported significant improvement.
Case 4. Erythema and white papules in the perianal area of a 38-year-old woman using moist toilet paper.
Methylchloroisothiazolinone/methylisothiazolinone (Kathon CG; Rohm and Haas, Philadelphia, Pennsylvania) is a widely used preservative in cosmetics and industrial products. Originally introduced to the United States in 1980, MCI/MI gained popularity because of its antimicrobial effects at very low concentrations and activity at a broad pH range.1,2 However, MCI/MI has been a well-documented cause of ACD, particularly in Europe, where restriction of its use as a preservative has been implemented because of increased sensitization.3 The North American Contact Dermatitis Group reported a prevalence of MCI/MI contact allergy of 2.8% in 2005 and 2006.4 A study at Mayo Clinic from 2001 to 2005 identified patients who underwent patch testing for suspected ACD. Of 3740 patients tested, 3.0% had a contact allergy to MCI/MI.5
Methylchloroisothiazolinone/methylisothiazolinone is a common preservative in moist toilet paper. Introduced primarily for baby hygiene, moist toilet paper now is also widely used by adults for their intimate personal hygiene. Perianal and perineal ACD due to MCI/MI-containing moist toilet paper has been rarely reported in the United States. Table 2 summarizes reported cases of ACD caused by MCI/MI in moist toilet paper. The present case series describes 4 persons seen over a period of 6 months who had perianal and perineal dermatitis from MCI/MI-containing moist toilet paper. Patch testing for these patients was conducted to the standard series in a uniform fashion using the same methods as described previously,5 and all allergens were in water, petrolatum, or alcohol. All of the patients had a positive allergic patch test reaction to MCI/MI. Furthermore, each patient reported resolution of symptoms after discontinuing use of the moist toilet paper.
Our cases illustrate several important points. First, patients with perianal lesions often continue to use the moist toilet paper with the belief that the cleansing will help heal the lesions; they may not make the correlation that the moist toilet paper is the culprit. For example, the patient in case 3 had perianal dermatitis for 20 years, which was initially thought to be part of his psoriasis. He never suspected the moist toilet paper as the cause of his condition. Within 6 weeks of withdrawing the causative brand of moist toilet paper, he reported a 99.9% improvement.
Second, misdiagnosis of this problem can result in unnecessary treatments and their concomitant potential adverse effects. The patient in case 2 likely had a misdiagnosis of pityriasis rubra pilaris, was started on methotrexate therapy, and had subsequent development of hepatotoxic effects.
Third, perianal ACD can be extremely uncomfortable and debilitating. The patient in case 1 missed 2 months of his work as a mail carrier because of the severity of his ACD. These examples demonstrate the importance of specifically asking patients with perineal or perianal dermatitis about moist toilet paper use and educating them about the potential for ACD.
It is also important to acknowledge that, although in our cases MCI/MI appeared to be the causative allergen, moist toilet paper may contain other documented ACD-causing ingredients such as quaternium 15, iodopropynyl butylcarbamate, DMDM hydantoin, and various fragrances.8 Therefore, it cannot be assumed that all ACD caused by moist toilet paper is due to MCI/MI. A list of ingredients in Cottonelle moist toilet paper is provided in the following tabulation.
Sodium lauryl glucose carboxylate
Aloe barbadensis leaf juice
This study has some limitations. For example, neither patch testing nor use tests were performed on our patients with the suspect brands of moist toilet paper. A use test involves applying the suspected product to a small area of skin to see if it elicits a reaction. Performing these tests would have allowed us to more definitively link the ACD to the moist toilet paper. In addition, because all of our patients were prescribed topical corticosteroids for treatment, it is difficult to quantify to what extent the patients' improvements were indeed from discontinuation of the moist toilet paper. However, before being seen at our clinic, all of our patients had tried topical corticosteroids to relieve their symptoms. Although they reported some relief with these earlier treatments, the relief they reported after they stopped using the moist toilet paper was far greater.
In conclusion, perianal and perineal ACD caused by moist toilet paper containing MCI/MI is probably more prevalent in the United States than once thought. The growing popularity of moist wipe use among adults increases the risk of exposure and potential sensitization, especially on mucosal surfaces. Along with others, we voice our concerns about MCI/MI being used as a preservative in cosmetics, industrial products, and moist toilet paper. Perianal and perineal dermatitis caused by moist toilet paper may be unrecognized and/or misdiagnosed, causing chronic discomfort and disability for many patients. Dermatologists and other health care providers must be made aware of the hazards of MCI/MI-containing moist toilet paper, and they must then educate their patients regarding alternatives and stress the importance of label reading.
Correspondence: Mark D. P. Davis, MD, Department of Dermatology, Mayo Clinic, 200 First St SW, Rochester, MN 55905 (firstname.lastname@example.org).
Accepted for Publication: February 21, 2010.
Published Online: June 21, 2010. doi:10.1001/archdermatol.2010.114
Author Contributions: Dr Davis and Mr Gardner had full access to all of the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. Study concept and design: Gardner, Davis, Richardson, and Pittelkow. Acquisition of data: Gardner, Davis, Richardson, and Pittelkow. Analysis and interpretation of data: Gardner, Davis, and Pittelkow. Drafting of the manuscript: Gardner, Davis, and Pittelkow. Critical revision of the manuscript for important intellectual content: Davis, Richardson, and Pittelkow. Obtained funding: Davis. Administrative, technical, and material support: Gardner, Davis, and Richardson. Study supervision: Davis and Pittelkow.
Financial Disclosure: None reported.
Thank you for submitting a comment on this article. It will be reviewed by JAMA Dermatology editors. You will be notified when your comment has been published. Comments should not exceed 500 words of text and 10 references.
Do not submit personal medical questions or information that could identify a specific patient, questions about a particular case, or general inquiries to an author. Only content that has not been published, posted, or submitted elsewhere should be submitted. By submitting this Comment, you and any coauthors transfer copyright to the journal if your Comment is posted.
* = Required Field
Disclosure of Any Conflicts of Interest*
Indicate all relevant conflicts of interest of each author below, including all relevant financial interests, activities, and relationships within the past 3 years including, but not limited to, employment, affiliation, grants or funding, consultancies, honoraria or payment, speakers’ bureaus, stock ownership or options, expert testimony, royalties, donation of medical equipment, or patents planned, pending, or issued. If all authors have none, check "No potential conflicts or relevant financial interests" in the box below. Please also indicate any funding received in support of this work. The information will be posted with your response.
Some tools below are only available to our subscribers or users with an online account.
Download citation file:
Web of Science® Times Cited: 8
Customize your page view by dragging & repositioning the boxes below.
The Rational Clinical Examination
All results at
Enter your username and email address. We'll send you a link to reset your password.
Enter your username and email address. We'll send instructions on how to reset your password to the email address we have on record.
Athens and Shibboleth are access management services that provide single sign-on to protected resources. They replace the multiple user names and passwords necessary to access subscription-based content with a single user name and password that can be entered once per session. It operates independently of a user's location or IP address. If your institution uses Athens or Shibboleth authentication, please contact your site administrator to receive your user name and password.