How to treat an aphthous ulcer at back of throat?

Palliatively: Really only to alleviate symptoms. An aphthous ulcer is self limiting and will go away in a week with treatment and seven days without. The problem is comfort. Topical ora gel can help.

Ulcers last 1-2weeks: Ulcers usually last one to two weeks. Avoid irritating the area and try over the counter medication!

Canker sores: The most common observable lesions in the oral cavity and back of the throat. Individual ulcers typically last 7-10 days. The topical anesthetic otc application is recommended. In your case use a long q-tip for the application. Rec.: see your pcp if concerned.