I’ve been in and out of the US and Central America this way. The test is in my CPAP bag. NEVER piut syringes in the carry on though, that will get you pulled quick. Bottom line, they don’t care. Especially if it’s just a few weeks worth of TRT dose.
How do people with diabetes do it if syringes will get you pulled? Honestly I just put them and the T vial in a plastic bag and just put it in one of the bin things with my wallet etc and I’ve never gotten asked about it. Which is honestly kind of crazy now that I think about it considering they have no idea what’s in that vial
I’ve traveled to the Caribbean and Canada and I carry all my test supplies in a diabetic organizer syringes and all in my carryon and have never had an issue.
If you are concerned about the syringes being confiscated I would carry more in my check baggage just in case.