You can use any type of containers (plastic, glass) to hold your liquids/gels as long as each one does not exceed a capacity of 3.4 oz (100 ml). You can take as many of those containers as will fit in 1 quart size zip-lock bag.

Regarding your OTC and prescription drugs - liquid/gel medicines will have to comply with the size restrictions and fit in your ONE zip-lock bag. As for pills, many people will tell you to take them in their original containers or at the very least bring along a copy of your prescription but I've travelled extensively around the world and carried pills in various size and types of containers (mostly those 7-day pill cases and/or ziplock bags) and no one has ever even battered an eyebrow let alone questioned me about them.

It's not a major issue unless you are carrying hundreds or thousands of drugs.

The containers/bottles don't have to be marked for TSA/security. But you just might want to put labels on them. That shampoo/conditioner/whatever can all look alike in those little bottles.

Lost a 4 oz bottle of Pepto not long ago should have been tabs

Containers are fine as long as 3 oz prescription meds

do not mix and clear labels or customs in some countries

rarely will confiscate them.

If traveling with controlled or scheduled drugs bring

MD record of medical need and pharmacy records to be safest.

Happy Journey,

No (as long as the containers are not over 100 ml or 3 oz) and No (you can basically do anything you want with pills).

For the prescription meds, take a copy of the Rx label. I've never been questioned and I throw all kinds of OTC remedies into one divided container, but it never fails that if you don't have the label they'll ask for it. Most pharmacies will reprint a label for you so you don't have to try to peel one off of a bottle.

No one cares if they are marked or not. I agree with those who mentioned to label them for your own sake, so you know what's what and aren't using hand lotion as shampoo!

I have never been questioned about unlabeled prescription meds or ever once asked by anyone to see a prescription in several decades of traveling.

I always place the pills in a small plastic sack and put the prescription label on the sack. It's very easy to remove a label from a bottle and position it on the plastic sack. The plastic sacks I use come from a jewelry-making store.