Kindly mention wat symptoms are present. If it is only common cold or cough. If there is fever or not. If there is fever and accompanying symptoms then it is better to consult a doctor. For common cold give syrup matra 2.5 ml twice a day for 3 days.
Maxtra contains paracetamol and chlorpheniramine which is a antihistamine. It will cause a bit of drowsiness., Nausea,vomitting , palpitations n headache.
Next Steps
Give steam inhalation. If not better consult a doctor.