Hi. I hope you are feeling better by the time you read this. Asthma which gets worse at night, especially when lying down, could be signs of another problem. Of course, checking O2 sat is important, evaluation for Sleep Apnea, but also check out cardiac problems. There are increased signs of breathing difficulty when lying down, very often from congestive heart failure, or the beginnings of other cardiac diseases. Look for signs and symptoms such as leg swelling - either one or both, lymphedema, etc. If you do a nebulizer or inhaler, do you find that you can lie down better? If the nebulizer/inhaler are not helping, it could be a host of other issues. Do you have acid reflux or GERD - both of which can cause asthma symptoms, especially when laying down in bed. Do you take a diuretic? How many pillows do you use to sleep? More than 2-3 is considered orthopnea. Something which may help - until you get this further checked out is elevating the head of the bed on blocks, putting large pillows/blankets under the top of your mattress, using more pillows or getting a wedge. Careful with this, as it could cause neck pain. Please check it out and feel better.