Geri - the above suggestions are great.  When my husband and I went to Cancun a few years ago this is what I left with the babysitter.

1.  Instructions on giving normal daily meds.

2.  Instructions on when to give a stress dose and how much a stress dose is.

3.  What constitutes a crisis and what needs to be done.

4.  Emergency contacts - endocrinologist, pediatrician, family members who are   familiar with my daughter and CAH.

5.  A phone number where my husband and I could be reached in an emergency.

Also, I called both the endocrinologist and pediatrician and informed them that I would be out of the country and who would be caring for my child - just in case something came up and they got a call from this person.  Both doctors thought this was a great idea.

Be sure to leave all insurance info, cards, etc with the sitter.  Also, leave in writing some kind of permission for your sitter or someone there to authorize medical care for your child.  I still use a copy of a form I got from the hospital when my daughter was born.  I just keep extra copies in the desk and pull one out whenever I need it.

Lastly, go and have fun!  With all the daily stress we all face - plus the stress of dealing with CAH - it will do you good.  By the way, where in Mexico are you going?

Kay