I have to use drops for dry eyes but I have to take out my contacts for 10 minutes while I use them. If I don't use them, I blink my contacts out when I ride (and I'm blind without them...I couldn't get home). I don't think there is much of anything besides contact rewetting drops or plain old saline that you can use with the contacts still in.

There are some newer contacts that are made with water or gel in them that are supposed to keep your eyes from drying out? I can't remember the brand (I can't wear them b/c of eye allergies) but it might be something to ask your optometrist about.