What could be in those little viles sold everywhere on the streets of bangkok. All those fancy colours and funny letters on them? Are they some elicit drug? Some magic potion that makes you healthy? No, it's much simpler than that:
These little viles sold on the streets of Bangkok are contact lenses. Mostly fashion lenses with 0.0 magnification. Lots of big black pupil lenses (open pupils are a sign of love, so these fashion lenses often have big black pupils). Lots of odd colours and garish patterns for girls that want to look different.
Be careful when you buy them, your eye lens needs to breath, and contact lenses should not be left in, should be kept in the proper cleaning solution and thrown away after their stated lifespan because they clog up with bacteria. Best to read up on usage of contact lenses before you try them out.
A lot of the problems people have with these contact lenses is simply because they've never had real contact lenses and don't know the pitfalls.