I see at least one other person has had the same problem I did in posting somewhat longer messages here.
I don't know if it's a passing issue with MedHelp's tech set up, but rather than lose a long message you've prepared, try this:
You will see a blank screen, which says MESSAGE TOO LONG or something like that in the upper right corner of a page that pops up.
Click the 'back' button on your browser, and it should take you back to the screen where you typed in your message into the little message box.
Then highlight and copy your entire message, and go paste it into a Word document or a regular email message. Save it.
Then highlight a small portion of the message, copy it, and then paste the copied portion into the message box back at MedHelp. After that, type something like 'continued in next message', and hit send.
If you get the same 'too long' message, then try again, using a shorter chunk of your original message.
((I think MedHelp may have been doing system maintenance or bug-fixing that was causing this problem, but not sure. I have also heard that MedHelp objects to posters like us pasting long chunks of text from other sources (maybe a copyright ownership issue). My thought was that an automated system counted up my words and decided I had too many of them, or something. Dunno. It doesn't seem to be happening today.))