A general rule. If they grab your pack it is almost for sure at random or something was really off with the pack, or they got a very specific tip.
At that point they will decide if whatever is inside is worth the effort, expense, and trouble to go after you and track that pack. That is not common with most things that we order.
At that point, with the new tech and the fact that the people that do this in LE do it all the time and have perfected the process, it is very unlikely any amount fancy tricks you try will save you.
Prior to arrival, CBP gets an electronic file with a ton of info about every pack in a given container. Sender, recipient, declared contents, even x-rays from the departing side. 40+ data fields. It was complying with the requirement for more advance data that caused all the foreign post offices to suspend packs to the US earlier this year. Only a handful had their software upgraded in time to provide the data required,
An algorithm decides if there’s enough “suspicious points” to pull the entire container for inspection.
98% of containers are “electronically cleared” and bypass customs all together, but if they pull a container, and your pack is in it, there’s a pretty good chance it’s getting seized, whether you were one of the suspicious ones or not.
That said, CBP is getting hundreds of billions in new funding in 2026. That may mean they’ll be able to pull much more than just 2% of containers for detailed inspection in the future.
IMO, you should never assume you’ll be able to get this stuff indefinately. Best practice is to build a buffer supply of anything that you don’t want to live without. I think at least 2 years is reasonable. Most medications, with only a few exceptions, can remain potent for over 10 years. The great all aluminum packaging from India, designed to preserve drugs in their tropical environment, is ideal for long term stash storage.