Psoriasis is a common chronic inflammatory disease with an incidence of about 0.5-3 %. Previously
psoriasis was not primarily regarded to be associated with
pruritus; however, this perception has changed in recent years. Meanwhile data conclusively show that between 64 and 97 % of patients report about
pruritus that can be severe in a number of cases. Apart from suffering from
psoriasis, the presence of
pruritus causes additional stress and leads to a significant impairment of health-related quality of life.
Neurogenic inflammation at least in part contributes to the development of
pruritus in
psoriasis skin lesions. A number of
neuropeptides including substance P and
calcitonin gene related peptide can act as pro-inflammatory mediators. There is evidence for a dysbalance between κ‑ and µ‑opioid receptors in lesional skin favoring
inflammation and
pruritus. After clearing of
psoriasis lesions,
pruritus is relieved as well. Therefore, specific treatment of
pruritus is not necessary in general. In cases where severe
pruritus is a prominent symptom, targeted
therapy with mirtazapin or
doxepin or
neuroleptic compounds such as
pregabalin or
gabapentin or drugs affecting the κ‑ und µ‑opioid receptor balance can be administered. Today the importance of
pruritus as a prominent symptom of
psoriasis lesions has been widely accepted. In recent and running clinical trials with new drugs,
pruritus at baseline and the effect of these drugs on
pruritus is always assessed. This awareness also fuels basic research about
pruritus in
psoriasis.