Here's an article on that very subject:
tinyurl.com/35aqjk
This is a TSA page on flying with medications,
tinyurl.com/kv3uv
The bottom line, according to the TSA is
"if the liquid medications are in volumes larger than 3 ozs each, they may not be placed in the quart-size bag and must be declared to the Transportation Security Officer. A declaration can be made verbally, in writing, or by a person's companion, caregiver, interpreter, or family member. Declared liquid medications and other liquids for disabilities and medical conditions must be kept separate from all other property submitted for x-ray screening."
And:
Disability-related items permitted through the security checkpoint include:
# Augmentation devices (A catheter is an augmentation device)
# Ostomy supplies
So just keep it separate and declare it when going through security. Believe me, these security people deal with many, many people in the same situation you're in. It shouldn't be a problem at all.