Sugary drinks on plane?

So I'm flying on sunday and I just realised something I didn't think about.

I have a letter from my doctor but I wasn't sure if I'd be allowed to take my sugary drinks in my hand luggage. I have these little bottles called glucojuice and I also take lucosade sometimes. I don't know why but I just started worrying that they wouldn't let me take them.

I've never been on a plane before by the way.