Psoriasis is a chronic immunological skin disease and patients with this disorder typically experience a significant decrease in their quality of life. The disease is traditionally managed with topical and systemic agents (retinoids, ciclosporin A, methotrexate), but these treatment options are often long-term and their effects can be inconsistent and not ideal. The use of biological drugs in dermatological treatment is relatively new and began in the early 2000s. It should be noted that, in most countries, in order for biological treatment to be administered, specific criteria must be met. The current treatment options for psoriasis and psoriatic arthritis include tumour necrosis factor alpha (TNF-α) blockers, interleukin (IL)-12 and IL-23 inhibitors, T cell inhibitors and B cell inhibitors. These classes of biological drugs are characterised by protein structure as well as high molecular weight and their effectiveness is evaluated based on the Psoriasis Area and Severity Index (PASI), Body Surface Area (BSA) and the Dermatology Life Quality Index (DLQI). TNF-α antagonists are one such class of biological drugs which includes infliximad, etanercept and adalimumab. Infliximab is a chimeric protein that is administered via intravenous infusions as a monotherapy in psoriasis vulgaris. Etanercept is indicated for use in both psoriasis vulgaris and psoriatic arthritis and it is the only drug that can be used as a treatment for children under the age of 8 with psoriasis. The drug is administered subcutaneously. Finally, adalimumab is a fully human monoclonal antibody that neutralises both free and membrane-bound TNF-α and is used in the treatment of psoriasis vulgaris and psoriatic arthritis. This article reviews the latest research in the use of TNF-α for the treatment of moderate to severe psoriasis and psoriatic arthritis. The results of research in this field are promising and confirm the effectiveness and safety of biological drugs as dermatological treatments for psoriasis. In particular, adalimumab, etanercept and infliximab are promising therapeutic options for patients with moderate to severe psoriasis and psoriatic arthritis who are unresponsive to conventional treatment strategies and they can significantly improve the quality of lives in patients with this disease.