Lemsip Cold & Flu Sachets contain a combination of ingredients which are effective in relieving the symptoms associated with colds and flu, including relief of aches and pains, nasal congestion and lowering of temperature. Paracetamol is a well-known painkiller (analgesic). It is effective against aches and pains, including a headache, and can also reduce a fever (antipyretic). Phenylephrine hydrochloride (nasal decongestant) reduces swelling in the passages of the nose, relieving nasal congestion and reducing the pressure which may cause a headache. Lemsip Cold and Flu Lemon makes a soothing hot drink to relieve colds and flu symptoms such as headache, high temperature and runny nose