They technically allow large bottles of contact solution in carry-on because it's a medical necessity (https://www.tsa.gov/travel/security-screening/whatcanibri

They technically allow large bottles of contact solution in carry-on because it's a medical necessity (https://www.tsa.gov/travel/security-screening/whatcanibring/items/contact-lens-solution https://www.tsa.gov/travel/security-screening/whatcanibring/...). I just keep it in my toiletries bag and they pull it out to run a quick test most of the time.