Cosentyx is a prescription medication used to treat plaque psoriasis, psoriatic arthritis, and ankylosing spondylitis. According to the sources provided [1][2][3], common side effects of Cosentyx include upper respiratory infections, diarrhea, and nasopharyngitis. Additionally, patients may experience reactions at the injection site, such as redness, itching, or swelling. Other potential side effects include headaches, high blood pressure, and liver function abnormalities. Patients should contact their healthcare provider if they experience any serious side effects, such as allergic reactions, infections, or changes in vision. It is important to note that not all patients will experience side effects, and the severity and frequency of side effects may vary. Patients should discuss any concerns or questions about Cosentyx with their healthcare provider.

Sources:
[1] https://www.drugpatentwatch.com/p/biologics/tradename/COSENTYX
[2] https://www.cosentyx.com/safety-and-side-effects
[3] https://www.drugs.com/cosentyx.html