Y55: Agents primarily acting on smooth and skeletal muscles and the respiratory system

Y55.4: Expectorants

Y55.4 in the ICD-10 WHO 2016 classification refers to adverse effects in the therapeutic use of expectorants. Expectorants are medications used to treat conditions where mucus builds up in the airways, such as the common cold, bronchitis, and other respiratory conditions. They work by thinning and loosening mucus in the airways, making it easier to cough up and clear the airways. However, like any medication, the use of expectorants can sometimes cause adverse effects. These can vary greatly in severity from mild to serious and can include symptoms such as nausea, vomiting, or allergic reactions like skin rash, itching, and swelling. In severe cases, the adverse effects can negatively impact the respiratory system's normal function, sometimes causing difficulty breathing.