Most types of beer are made from barley, and many others are made with wheat.
It is these two gluten-containing ingredients that put most beer off limits for celiacs and those with a gluten allergy (the two main reasons people go on a gluten free diet).
And what if you are allergic to wheat?
If wheat, rather than gluten is your main problem, then you have more choices. You can probably buy your beer in at your local shop, being careful to read the ingredients to make sure the beer contains no wheat.
If unsure, contact the beer brewing company. Of course they may have a website, but I advise you to phone them, as you will likely get better information, and use less of your time finding it.
Depending on how sensitive you are to wheat, you will want to know if they keep wheat-free brands of beer separate from any brands or varieties of beer brewed with wheat. You are also verifying that the stated ingredients are correct and current. While unlikely, you do want to make sure that the brewer has not changed the recipe and failed to update the label.
If you are on a gluten free diet, then most beers will be problematic for you. As stated in the opening of this article, most beer is made with either barley or wheat.
The market is starting to catch up. Specialized gluten-free beer is starting to appear on the market to meet the demand for those on a gluten free diet.
For those who just have to avoid wheat, gluten free beer is perfectly safe for you.