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Lying in a variety of poses will help loosen phlegm and allow you to cough up mucous. First, lie on your back and prop pillows under you to elevate your hips. Then, lay on your right side with 2 pillows under your right hip. Rotate, and lay on your left side with 2 pillows under your left hip. Finally, lay on your stomach with 2 pillows under your hips.  Stay in each position for 5–10 minutes. The medical term “postural drainage” simply means adjusting the position of your body so that phlegm can drain from your lungs. While reclining in each position for postural drainage, breathe by expanding your stomach. Rather than focusing on breathing high in your chest (which may cause a coughing fit), focus on breathing low in your stomach. This will help the phlegm drain from your lungs.    Press out your stomach as far as it will go, and then imagine that you’re trying to fill that entire space with air when you inhale. The medical term for this type of breathing is “belly breathing” or “diaphragmatic breathing.” If the postural draining doesn’t loosen up your phlegm, you may need to physically loosen up the congestion. Cup one of your hands and tap your chest and back with about as much force as you’d use to crack an egg. Avoid tapping directly on your sternum or on your spine. You may need to ask a friend or family member to help you tap hard-to-reach parts of your chest and back. As you tap your chest and recline for postural drainage, phlegm and mucous will begin to loosen in your lungs. To cough up phlegm, sit down and lean slightly forward in a chair. Fold your arms over your stomach, and lean forward. As you press down on your stomach, cough 2 or 3 times. Pause for a few seconds, and then repeat.  As the phlegm comes up from your lungs, spit it out into a tissue, trash can, or other nearby receptacle. Practice controlled coughing to avoid coughing fits, which often cause your trachea and other airways to constrict.
Recline in different positions for postural drainage. Breathe deeply from your stomach while draining your lungs. Tap on your chest and back to loosen up phlegm. Practice controlled coughing.