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Q: I have woken up a few times in the past couple months gasping for  breath. It feels like my airway is blocked. I gasp really hard and it wakes me up. The gasp is so loud that it makes my husband nervous. I have allergies and quite frequently my sinuses are clogged. So I can't breathe out of my nose, and have to sleep with my mouth open.  I also have asthma but haven't had an attack in months. (I don’t think these were asthma attacks.) Is my throat blocked because of post-nasal drip or could it be something more serious like sleep apnea?

A: You are right on target with your two thoughts about what might be causing this shortness of breath that wakes you up.

Post nasal drip could cause secretions to migrate down your throat. To protect our airways, we have sensors in our throats and bronchial tubes. Foreign matter in our airways triggers the sensors to send a signal through nerves connected to the brain. The brain responds by sending messages back to the diaphragm and chest muscles to cough and breathe. Naturally this wakes us up, which is a good thing.

Sleep apnea also could cause the symptoms you describe. You don’t mention that your husband complains about heavy snoring, a characteristic of most people who have sleep apnea.

Other clues that would suggest sleep apnea:

Another condition that can cause a person to suddenly wake up because of shortness of breath is heart failure. Doctors call this paroxysmal nocturnal dyspnea. This symptom does not occur in isolation. People with heart failure will have decreased exercise tolerance, meaning they become particularly short of breath with exertion, especially with climbing stairs. Often there is new ankle and leg swelling.

Normally I would also include asthma as a possible cause of your problem. However, you said these gasping attacks feel different and you did not mention wheezing. Therefore, it is unlikely that gasping episodes are asthma flares.

By the way, some people with asthma don’t realize they are wheezing. They may only notice coughing or shortness of breath.

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