Rated 4 out of 5 stars

Easy to install and useful. Sometime bizarre (e.g. no "myocarditis" "bronchopneumonia" "osteoclast" but include "myocarditic", "osteoclastic" in the dictionary). It will nice if the raw file of dictionary can be edited directly.

This review is for a previous version of the add-on (1.0.8). 

Thanks for the comments and the words to add!

The dictionary file name is OpenMedSpel.dic and it can be edited with any text editor.

The raw dictionary file can be found in -
C:\Documents and Settings\**your account name**\Application Data\Mozilla\Firefox\Profiles\id8ro0eb.default\extensions\openmedspel@e-medtools.com\dictionaries