Pustular psoriasis is an unusual form of psoriasis that frequently presents 
clinical challenges for dermatologists. The condition presents with pustules on 
an erythematous background and has two distinct subtypes: localized disease on 
the palms and soles, called palmoplantar pustulosis (PPP), and generalized 
pustular psoriasis (GPP). The involvement of the fingers, toes, and nails is 
defined as a separate localized variant, acrodermatitis continua of Hallopeau, 
and is now thought to be a subset of PPP. The rarity of pustular psoriasis 
frequently makes the correct diagnosis problematic. In addition, treatment is 
limited by a relative lack of evidence-based therapeutic options. Current 
management is often based on existing therapies for standard plaque psoriasis. 
However, there remains a need for treatments with high, sustained efficacy and a 
rapid onset of action in pustular psoriasis. Recent advances in understanding of 
the pathogenesis of pustular psoriasis have provided insights into potential 
therapies. Treatment of pustular psoriasis is generally determined by the extent 
and severity of disease, and recent years have seen an increasing use of newer 
agents, including biologic therapies. Current classes of biologic therapies with 
US Food and Drug Administration and European Medicines Agency approval for 
treatment of moderate-to-severe plaque psoriasis in the USA (and elsewhere) 
include tumor necrosis factor alpha inhibitors (adalimumab, certolizumab pegol, 
etanercept, infliximab), interleukin (IL)-17 inhibitors (brodalumab, ixekizumab, 
secukinumab), an IL-12/23 inhibitor (ustekinumab), and IL-23 inhibitors 
(guselkumab, risankizumab, tildrakizumab). Recently, specific inhibitors of the 
IL-36 pathway have been evaluated in GPP and PPP, including spesolimab, an IL-36 
receptor inhibitor which has shown promising results in GPP. The emerging drugs 
for pustular psoriasis offer the possibility of rapid and effective treatment 
with lower toxicities than existing therapies. Further research into agents 
acting on the IL-36 pathway and other targeted therapies has the potential to 
transform the future treatment of patients with pustular psoriasis. This article 
reviews the clinical features of PPP and GPP, and current understanding of the 
genetics and immunopathology of these conditions; it also provides an update on 
emerging treatments.