Tossex New Syrup contains codeine 10 mg and triprolidine 1.25 mg. It is a controlled cough medicine and should not be used for self‑treatment or chosen on your own. A chest cough with fever can be due to viral flu, acute bronchitis, pneumonia, or other medical conditions, and the right treatment depends on a proper medical evaluation of the cause. It is safer not to start this medicine without a doctor’s assessment, because cough suppressants may not be suitable in chest infections, and fever suggests an underlying infection that may need different management. You should consult a doctor for examination and appropriate treatment, especially if there is a high fever, breathing difficulty, chest pain, or worsening symptoms.