According to the sources provided, skin irritation is a possible side effect of Cosentyx (secukinumab). The drug is used to treat plaque psoriasis and other autoimmune diseases by targeting and blocking a specific protein in the body that causes inflammation [2]. However, some patients may experience adverse reactions, including skin irritation, itching, and rash [3]. It is essential to inform your healthcare provider if you experience any side effects while taking Cosentyx. They may adjust your dosage or recommend alternative treatments based on your medical history and current condition [2]. In conclusion, skin irritation is a potential side effect of Cosentyx, and patients should discuss any concerns or symptoms with their healthcare provider [1][2][3].

Sources:
[1] https://www.drugpatentwatch.com/p/biologics/tradename/COSENTYX
[2] https://www.cosentyx.com/plaque-psoriasis/how-cosentyx-works
[3] https://www.webmd.com/drugs/2/drug-167673/cosentyx-subcutaneous/details