Sunscreen! Korea and Japan have great sunscreens that don't feel oily or icky on your skin because they're able to use more modern ingredients. The FDA hasn't approved new sunscreen ingredients since 1999.

This is important for people (commonly women) who regularly use skincare treatments that make their skin extra sensitive to the sun. They want daily facial sunscreen that doesn't feel greasy. We end up buying it on eBay because it's not allowed to be sold in the US.

For the longest time, something as simple as Voltarin was not available OTC in the US, but could easily be obtained from other countries. It's an anti-inflamatory cream used for joint pain that you don't have to eat, so lower risk of side-effects to stomach, liver, and kidneys.

Modafinil is one.