"We sold about 6,000 bottles," he recalls. "We always had a money-back guarantee. Only two to three customers asked for their money back. For one, it was because he didn't like the vanilla scent."
Calls to the Vero Labs, the Boca Raton, Fla.-based makers of Liquid Trust, were far less conclusive. As an automated voice in a distinctively clipped British accent ushers callers through mailbox options, they learn that Liquid Trust is "The world's first and only trust-enhancing spray, specially formulated to increase trust in you."
Messages left at the number were not returned.
Zak says the last time he encountered a representative of Vero Labs, it was on a morning news show on which he and a spokesperson for the company were both guests. Zak says he took this opportunity to point out that the company could face trouble from the FDA for marketing its product in the way it had.
"We really laid into them," he says.
Could the time come when a shot of oxytocin into the sinuses has therapeutic value? Some experts think it might. But even if such a treatment comes to pass, experts agree that boosting the hormone can only go so far when it comes to treating such complex issues as social anxiety and lingering psychological trauma.
"Social dysfunction and other antisocial behaviors are often very difficult to treat," Zak says. "There is often some trauma in these people's lives; these are hard patients to treat."
Plus, Seibel notes, oxytocin taken without a doctor's guidance can be harmful.
"You might be putting yourself at a significant risk," he says, adding that the drug could lead to miscarriage in pregnant women or heart problems in those predisposed to such conditions.
"I don't think that it's a good idea for the public to go out and get oxytocin on their own," he says. "I don't think there's enough evidence for us to know how powerful an effect this actually has."
So when it comes to Liquid Trust, do people need a dose of liquid skepticism instead? Zak says perhaps.
"There's probably a big placebo effect. ... It's not a crutch for people who are nervous," he notes. "Having said that, our findings are very exciting. Hopefully, people will just get the straight story and not the hype."