“When you see it, well, it sure makes a believer out of you,” said Representative Charles Anderson of Waco, a Republican state lawmaker who is sponsoring one of several bills to ban salvia in Texas.

When the federal government this year published its first estimates of salvia use, the data astonished many: some 1.8 million people had tried it in their lifetimes, including 750,000 in the previous year. Among males 18 to 25, where consumption is heaviest, nearly 3 percent reported using salvia in the previous year, making it twice as prevalent as LSD and nearly as popular as Ecstasy.

Recent studies at college campuses on both coasts have yielded estimates as high as 7 percent. The herb’s presence on military ships and bases has prompted enough concern about readiness that the Armed Forces Institute of Pathology was asked to develop the first urinalysis for salvia and is now testing 50 samples a month.

Image Brian D. Arthur is founder of Mazatec Garden, which sells salvia and other herbs online. Credit... Michael Stravato for The New York Times

Though research is young and little is known about long-term effects, there are no studies suggesting that salvia is addictive or its users prone to overdose or abuse. Indeed, a salvia experience can be so intense, and at times so unsettling, that many try it just once, and even devotees use it sparingly.

Reports of salvia-related emergency room admissions are virtually nonexistent, likely because its effects typically vanish in just a few minutes.

With little data at its disposal, the Drug Enforcement Administration has spent more than a decade studying whether to add salvia to its list of controlled substances, as is the case in several European and Asian countries. In the meantime, 13 states and several local governments have banned or otherwise regulated the plant and its chemically enhanced extracts.