Why is it that congestion clears up when you are standing but comes back sitting or lying down?

When you are in an upright position, gravity helps to drain mucus from your sinuses and nasal passages. This can relieve congestion and make it easier to breathe. However, when you lie down, gravity can cause mucus to pool in your sinuses and nasal passages, which can lead to congestion and difficulty breathing.

In addition, lying down can also cause your airways to become more narrow, which can further increase congestion. This is because the muscles in your throat and tongue relax when you lie down, which can allow the tissues in these areas to collapse and block your airway.

If you are experiencing congestion, there are a few things you can do to help relieve it. You can try using a nasal decongestant or saline spray, or you can take an over-the-counter antihistamine. You can also try using a humidifier to add moisture to the air, which can help to thin mucus and make it easier to breathe.