Tom, the oracle that is Mrs 38th asked if you'd been eating acidic food and gulping it down.She suggests that, providing you are confident that it is not anything too serious and that you are not on any prescribed medication, you could try something called Centaurium which is a herbal remedy - treats gastric reflux, heartburn and hiatus hernia etc. Lay off alcohol too. Available from good Health Food stores. She knows her onions does Mrs 38th and she has great rapport with Doctors in our area.