What Causes Burning Feeling In Esophagus While Treating Gastritis?

Hi I am taking Lansoproazol for gastritis and bile problems after endoscopy results to show I had these problems. I get a burning in my osephegus and also back of my tongue. The tablets do help but unfortunately they also make me extremely dizzy but more worrying that are making my heart beat in a strange way, sort of sudden heavy beats that make me feel sick. Is this normal?