Very interesting discussion here. Would also wonder if the problem might run in families or have a herditary component in some cases.

If a herbal supplement like St. John's Wort can do the trick, then advantages include easier availability without a prescription (at least in the U.S.; other countries may be a different story on availability), and not having risk of dependency as with benzodiazepines or potential difficulty getting them across borders and back.

Kava and valerian also are mentioned as relaxing agents, but with anxiety involved usually it's SJW pointed to first among the herbals.