Assessing Treatment of Pruritic Scalp

Pruritic scalp has not traditionally been specifically categorized as a separate dermatologic condition; but rather it has been included within the broad category of seborrheic dermatitis. This has severely limited testing and understanding of this entity. The objective of this study was to assess patient satisfaction with various topical and oral therapies for pruritic scalp. For this purpose, an open-label, five-week study, 12 patients with pruritic scalp were given five different therapies, each to be used for one week. The participants then completed a survey to assess their opinion on the different therapies. No one treatment was universally preferred. Lanacaine solution and steroid solution achieved slightly higher marks. In a few cases, oral antihistamines proved curative. In short, pruritic scalp is a distinct condition in which one experiences episodic itching of the head without any visible or pathological sign of psoriasis, head lice, or any other scalp disorder. The divergent responses in this study underlines that there are probably different factors and trigger points which elicit the condition. More studies on this entity are warranted. Pruritus is defined as sensations which provoke the desire to scratch. If there is no visible sign for the symptoms, one can use the term essential pruritus, pruritus sine material, or generalized pruritus [1]. However, such a designation discredits patients who have an itch secondary to metabolic alterations, systemic disease, or defect in the cutaneous neuroanatomy and neurophysiology. On this latter point, the anatomical framework for nerve conduction includes cutaneous elicitation of itch via pruritoceptive nerve fibers and their transmitters, spinal processing of the signal, and spino-thalamico-cortal transmission of the acknowledgement of the sensation. Nerve endings and neurotransmitterss can be primary causes of pruritus. The induction of pruritus with proteinases and cytokines demonstrates the close connections between immune and neurotrophic factors in the pathophysiology of pruritus. The scalp appears to process itch sensations slightly differently than other skin locations. The sensitivity of human scalp skin to pruritic stimuli by intradermal microdialysis in vivo is altered due to a lower innervation density of pruritic nociceptors and different central processing of itching [2]. Of note, atopic dermatitis also has been shown to have an alteration in histamine-sensitive nerve fibers [3]. Additionally, the scalp also has been shown to have an increased density of lymphatic vessels when compared to glabrous skin [4]. The lower venous and filtration pressure of the scalp leads to a diminished transcapillary protein extravasation [5]. A reduced vascular and sensory sensitivity of scalp skin to *Address correspondence to this author at 5600 Monroe Street, Suite 106B, Sylvania, Ohio 43560, USA; Tel: 419-885-3403; Fax: 419-885-3401; E-mail: [email protected] pruritic agents has been established [2]. Patients with dandruff have been shown to have decreased levels of intercellular lipids in the scalp stratum corneum and impaired barrier function [6]. We propose that pruritic scalp be designated a distinct condition in which one experiences episodic itching of the head without any visible or pathological sign of psoriasis, head lice, or any other visible cause of irritation. Textbooks place this condition within the broad category of seborrheic dermatitis which classically present with dandruff and greasy scales of the hairline and eyebrows. This pilot study was performed to assess patients’ responses to various topical therapies in cases of pruritic scalp.