Sarcoidosis is a systemic granulomatous disease that affects numerous organs, commonly manifesting at the lungs and skin. While corticosteroids remain the first line of treatment, tumour necrosis factor alpha (TNF‐α) inhibitors have been investigated as one potential steroid sparing treatment for sarcoidosis. TNF‐α is one of many components involved in the formation of granulomas in sarcoidosis. While there have been larger scale studies of biologic TNF‐α inhibition in systemic sarcoidosis, studies in cutaneous disease are limited. Paradoxically, in some patients treated with biologic TNF‐α inhibitors for other diseases, treatment can induce the development of sarcoidosis. In the light of this complexity, we discuss the role of TNF‐α in granuloma formation, the therapeutic role of TNF‐α inhibition and immunologic abnormalities following treatment with these TNF‐α inhibitors including drug‐specific alterations involving interferon‐γ, lymphotoxin‐α, TNF receptor 2 (TNFR2) and T‐regulatory cells.