How long will throat swelling remain after bee sting?

There should be none. Ideally there should be no throat swelling. Anaphylactic shock can be thought of as a triad of symptoms including hives, respiratory difficulty (excessive throat swelling) and low blood pressure. The presence of one or two of these is an anaphylactoid reaction. Either should be evaluated by a doctor. Carrying an epi-pen and Benadryl (diphenhydramine) might be in order. Throat swelling can become dangerous quickly.