Went to the emergency room with asthma. doctor said i had acid reflux. what is acid reflux?

Natural event: Reflux is caused when the acidic stomach contents backwash up the swallowing tube. It is common & the equivalent of a super wet burp.It is aggravated by nicotine, caffeine or filling up and laying down, where gravity is not available to help keep the foods down. If it produces symptoms, acid reducers are often used to make the backwash less irritating. It can sometimes trigger asthma.

GERD: Acid reflux or gerd or heartburn is a condition when lower esophageal sphincter or muscular ring between the stomach and esophagus (feeding tube) becomes weak allowing stomach acid to leak back to esophagus, especially when laying down, when that happen at night time as you are laying down the acid from stomach can backflow as far as your lungs causing asthma symptoms.