Pityriasis Folliculorum: Response to Topical Ivermectin

December 2017 | Volume 16 | Issue 12 | Case Reports | 1290 | Copyright © December 2017

Kavita Darji BA and Nicole M. Burkemper MD

Saint Louis University School of Medicine, Saint Louis, MO

either facial erythema or pityriasiform squamous lesions.16 Individuals with both common rosacea and pityriasis folliculorum suffer from similar symptoms, including facial pruritis, flushing, pustules, and blepharitis.3 However, rough surface of the skin, often described as “sandpaper-like”, differentiates pityriasis folliculorum from common rosacea.3 Moreover, common rosacea manifests more often with oily skin, without follicular scaling, and occurs deeper in the skin.3,17There are various treatment options for human demodicosis (including pityriasis folliculorum), but overall this condition can be challenging to treat due to extensive survival of Demodex mites from a possible localized or systemic immune deficiency associated with pityriasis folliculorum, as evidenced by prior literature.9,18 Preferred therapy is ivermectin (200 μg/kg single dose), often used with topical metronidazole 1% gel, permethrin 5% cream, or benzyl benzoate.7,10 Ivermectin, a macrolide endectocide and an anaricidal, has both anti-inflammatory and anti-parasitic characteristics with efficacy against both endoparasites with cutaneous tropism and ectoparasites, such as D. folliculorum.14 A prior study showed improved appearance of demodicosis lesions within 3 months with a single dose of oral ivermectin 200 μg/kg and topical permethrin 5% lotion administered for 3 consecutive nights, with oral ivermectin repeated weekly for 10 weeks in addition to oral erythromycin and topical metronidazole cream.10 Additionally, significant response to treatment with oral ivermectin and 5% permethrin cream for Demodex infection was seen in an HIV positive male.19 Similarly, the combination of oral ivermectin (4 doses over 6 weeks) and topical permethrin resulted in extensive resolution of severe demodicosis located on the face within 3 months in a child with leukemia.15 Eucalyptus globulus, or camphor oil, with or without glycerol dilutions at concentrations of at least 50%, provided complete resolution, with no side effects.14,20 Although treatment with steroids may initially show improvement, long-term use exacerbates demodicosis lesions.15Ivermectin in its topical form has demonstrated efficacy in treating rosacea and was recently FDA approved for treatment of papulopustular rosacea.11,21-22 Ivermectin 1% cream is used topically once daily on regions of the face and neck containing rosacea lesions, and has minimal (<2%) incidence of adverse effects.23 Two prior clinical trials showed efficacy of ivermectin 1% cream in treating rosacea patients with decreased counts of inflammatory lesions, higher percentage of lesion categorization as “clear” or “almost clear” according to Investigator Global Assessment, and increased patient-reported outcomes of lesion improvement when compared to control patients who received the vehicle cream.11-13 Once-daily topical use of ivermectin 1% cream has displayed greater efficacy than twice-daily metronidazole 0.75% when treating rosacea, also measured using these same parameters.24 The positive response of pityriasis folliculorum to treatment with ivermectin 1% cream can be similarly measured by lesion reduction and patient satisfaction in our patient. Ivermectin therapy eliminated the rough red patches and “sand-paper like” texture in our patient, who herself reported improved skin lesions and was pleased with the outcome of therapy.To our knowledge, this is the first reported case of the use of ivermectin 1% cream for pityriasis folliculorum. As indicated by the reduced severity of skin abnormalities associated with this condition and patient contentment noted in this case, topical ivermectin 1% cream may be used for successful management of pityriasis folliculorum. Given that this condition can be very difficult to treat, having another treatment option could lead to improved control of this disease and better patient outcomes.


The authors have no conflict of interests to declare.