Its legal in the UK, and Iran properly has NO idea about it! as it is packaged I can just tell them its tea or some shit.
First think I'd do is go look up the penalties for drug use/smuggling in Iran and then decided if you really want to risk them knowing what it is or not![]()
The only safe place for salvia in a situation like that is in a condom inside your anus, sorry if i sound rude.