This information is for people who have GORD. It tells you about H2 blockers, a treatment used for GORD. It is based on the best and most up-to-date research.
Do they work?
Yes, if you have gastro-oesophageal reflux disease (GORD), taking drugs called H2 blockers can help symptoms, such as heartburn, and help heal your oesophagus (the tube that carries food from your throat to your stomach).
H2 blockers may not work as well as newer drugs called proton pump inhibitors.
What are they?
H2 blockers are drugs that aim to help your symptoms and heal any inflammation in your oesophagus.
Your doctor may ask you to try these drugs if your heartburn is fairly mild. You'll need a prescription to get full-strength H2 blockers. But you can get lower doses without a prescription. The tablets that you buy over the counter may help if you have mild heartburn or if you get it only now and again.
Some of these drugs (and their brand names) are:
At first, you'll need to take a tablet every day. Once your symptoms are under control, you may need to take a lower dose every day to keep your symptoms away. Doctors call this maintenance treatment. Or you may need to take a tablet only when you feel you need one. This is called intermittent treatment.
How can they help?
Taking this medicine each day can make you feel better. Some people find that it relieves uncomfortable symptoms, such as heartburn. And it may help inflammation or soreness in your oesophagus.
If you take these drugs you will probably get better more quickly than if you don't have any treatment. 
But H2 blockers don't work as well as proton pump inhibitors.  They are less likely than proton pump inhibitors to make your symptoms better or heal inflammation. And once you feel better and your oesophagus is not sore, H2 blockers do not work as well as proton pump inhibitors at stopping your symptoms coming back. So they are not so good for long-term treatment of GORD.  
How do they work?
H2 blockers work by reducing the amount of acid your stomach makes. Your stomach makes acid to help break down food and kill any germs that may have got into it. But when you have GORD, some of this acid flows into your oesophagus (the tube that carries food from your throat to your stomach). This is what causes your symptoms.
If you reduce the amount of acid in your stomach, you reduce the amount that can get into your oesophagus and irritate it. This makes it less likely that you'll get heartburn, gives inflammation a chance to heal, and keeps your condition from getting worse.