Coughnol-BM Syrup is a cough treatment that thins mucus in the nose, windpipe, and lungs, providing relief from runny nose, sneezing, itching, and watery eyes. It is taken with or without food, and the dose depends on the patient's condition. Common side effects include nausea, indigestion, bloating, diarrhea, headache, skin rash, and palpitations. It can cause sleepiness, so don't drive or engage in mental focus activities. Avoid alcohol while taking this medication. It's important to inform your doctor if you are breastfeeding or have kidney or liver diseases.