'A Frog in the Throat? Where from?

Have you ever wondered where the expression: ' Frog in the throat' came from? It's really strange and for any foreign student studying English this will probably raise his/her eyebrows because of such a saying. Well, here are a couple of common understandings you might find interesting.
There are a couple of explanations for this one:

One explanation says: it originated in medieval times when physicians thought that the secretions of a frog could help heal a sore throat. A live frog head was put into the patient's mouth, and the frog was believed to draw out the infection into its own body when it inhaled.

Another explanation is that years ago, people drank directly from ponds and streams, meaning there was always the fear that one could ingest an actual frog or frogspawn. It is believed that once the eggs hatched, one would experience a choking feeling when the young froglets were ready to come out. In the olden days, a travelling medicine merchant (i.e. quack) might have an assistant with a terrible cough (frog in the throat). As he administered a particular medicine supposed to cure all ills, the assistant would pretend to cough up a live frog, and then be pronounced cured.

Ahhhhhhhhhhhhhhhhhh, disgusting, imagine if it were true. : P