Myth: Itching is not a symptom of acne
Acne vulgaris typically is not considered to be a pruritic disease; however, many patients experience itching, which leads them to scratch their acne lesions, causing secondary bacterial infections and subsequent scarring, hypopigmentation, or hyperpigmentation of the involved skin. Although itching rarely is mentioned as a clinical feature of acne, pruritus can be an important contributory factor to the burden of disability and impaired quality of life in acne patients of all ages, and acne itching may be an important target for therapy.
In a descriptive study of 120 consecutive acne patients in Singapore, itch was found to be a common (70% of patients) and debilitating symptom of acne. The majority of patients (83%) reported itch at noon with severity that was comparable to a mosquito bite, and the most common physical descriptor was tickling (68%). Common aggravating factors included sweat (71%), heat (62%), and stress (31%). Fifty-five percent of patients said itching had a negative impact on their mood, and 52% reported that they had scratched or rubbed the affected area.
A study of 108 adolescents with acne limited to the face yielded half who reported itching within acne lesions. The presence of itching was unrelated to age, gender, where they lived, positive family history, or acne severity. In most patients, pruritus appeared relatively infrequently and for a short period of time: 7.4% reported itching every day, 24.1% on a weekly basis, 29.6% at least once a month, and 37.7% even less frequently. Itch episodes lasted less than 1 minute in most participants. However, 31.5% of participants sought medical treatment to reduce itching. The most important factors aggravating the intensity of itching were sweat, stress, physical effort, heat, fatigue, and dry air, respectively.
Regarding the impact of acne itching on quality of life, 29.6% of participants felt depressed and 1.8% were anxious because of their itching. Some participants also noted that itching caused difficulties in falling asleep and awakening from itching.
The pathogenesis of localized itching in acne could be connected with the change in pH of the microenvironment of the acne follicle, providing an optimal environment for the production of histamine or histaminelike products by Propionibacterium acnes. Pruritus also may be a complication of certain acne therapies. Increased awareness among patients of this potential side effect may be helpful in preventing the unnecessary discontinuation of an otherwise effective acne therapy. Understanding factors that may aggravate itching in acne lesions also may be helpful to patients.