Phosphodiesterase 4 inhibitors
This is an anti-inflammatory oral treatment (tablets) that works by reducing enzymes in the body called phosphodiesterase 4 inhibitors (PDE4), which are involved in the inflammatory process seen in psoriasis and psoriatic arthritis. The drug reduces the skin plaques and improves swollen joints. Women of child-bearing age should avoid becoming pregnant while taking a PDE4 inhibitor. Discuss with your doctor which types of contraception are suitable for you and your partner.
The treatment does contain lactose. There have been reports of an increased risk that some people may experience psychiatric symptoms with PDE4 inhibitors, including depression and suicidal thoughts, therefore close monitoring is required.
The National Institute for Health and Care Excellence (NICE) has recommended that PDE4 inhibitors can be used if there has been no response to other systemic therapies, including ciclosporin, methotrexate and phototherapy (PUVA: psoralen and ultraviolet A light), or when these treatments are contraindicated or not tolerated.