Dermatological pharmacology: systemic drugs

Systemic treatment of skin disease continues to evolve with biological drugs (‘biologics’) and new small molecules. This has been made possible by a deepening understanding of the pathogenesis of inflammatory dermatoses and skin cancer at a molecular level. As well as a range of biologics for psoriasis, there are now licensed biologics for eczema, urticaria and hidradenitis suppurativa. Biologic therapy also offers the chance of improved survival for patients with advanced melanoma. Biologics and new drugs may be highly effective but their expense limits patient access to those with severe disease where other systemic treatments have failed or are inappropriate. Many patients with skin disease are therefore prescribed traditional immunosuppressive or anti-inflammatory medication. These drugs require careful patient selection, prescribing and monitoring for adverse effects to reduce the risk of harm. The prescriber also needs to be able to advise patients of the risks versus benefits of different treatment options so they can make an informed choice about their care.