My favorite spellchecker for any specialty work is Spellex. I’ve used the medical/pharmaceutical bundle for literally years. I particularly like the quarterly updates. There are spellcheckers for medical, legal, botany, biological sciences, medicine and pharmaceutical–among others.
I was trying to get the search box to show up here, but that will have to wait until later; meanwhile here is the link: Spellex Online medical spellchecker.
Great for what goes into actually making a book with the current technology.
Editing classes, useful tips, and a newsletter that is great for grammar refreshers.