I remember that one of the things my original neuro (the mg specialist, 30+ years ago) said I might be bothered with was dry eyes. As I remember, he said this was because basically we 'forget' to blink. Seems like it is less fatiguing to hold the eyelid open than to blink, that is, to close it and reopen it. Of course, without blinking, the eyes dry out.
I've been doing some research on it, and have not really found too much. I did find on one site that normal blinking rate is 10 to 20 times a minute, and I know I don't blink anywhere near that often. I did find the following very interesting info: "Do use eye drops and eye gels to relieve your eyes from becoming dry. Failure to close the eyes completely, sometimes leading to poor blinking, can result in the loss of the "windshield-wiper effect". Dust and dirt, therefore, are allowed to accumulate in the eye." That was from http://www.myasthenia.org.au/html/lifestyle.htm which , by the way, I found to be a really good site. I don't think my dry eyes are a result of Sjogren's, which can be secondary in myasthenics.
So my question is, have any others noticed a tendency to dry eyes? Do you seem to blink less than a normal person would?