I'm trying to figure out if there's a way to tell the difference between a cough that's from an infection and one that's because of fluid in the lungs. At first, my doctor gave me antibiotics and cough syrup, but they didn't help my cough. Then, when my coughing got really bad, I saw another doctor who gave me Lasix, and that actually worked right away. So, is there a way to know if a cough is more likely from fluid in the lungs rather than an infection? It would really help to understand if there's a distinct difference so I can feel more sure about what's causing my cough.