A nice trick that will help you save time and effort when spell checking a long text with lots of words unrecognized by Word. Let’s suppose that you have an 85-page medical text with unrecognized terms, such as etrolizumab and fresolimumab, repeated throughout the text. 

1) Locate the first instance of the term etrolizumab.
Normally Word won’t recognize it; instead it will display a red wavy line under the “unknown word.”
2) Make sure it has the correct spelling.
3) Right-click on it and select Ignore All.

This way, Word will ignore all correct instances of etrolizumab and it will only display a red wavy line under each misspelled instance of the term. Now, it should be easy for you to catch the misspelled etrolizumamb.