ANTWERP, Belgium—When the housing market crashed in 2008, David Llewellyn’s construction business went with it. Casting around for a new gig, he decided to commercialize something he’d long done as a hobby: making drugs.
But the 49-year-old Scotsman didn’t go into the illegal drug trade. Instead, he entered the so-called “legal high” business—a burgeoning industry producing new psychoactive powders and pills that are marketed as “not for human consumption.”
Mr. Llewellyn, a self-described former crack addict, started out making mephedrone, a stimulant also known as Meow Meow that was already popular with the European clubbing set. Once governments began banning it earlier this year, Mr. Llewellyn and a chemistry-savvy partner started selling something they dubbed Nopaine—a stimulant they concocted by tweaking the molecular structure of the attention-deficit drug Ritalin.
Nopaine “is every bit as good as cocaine,” says Mr. Llewellyn, who has lived in Antwerp on and off since the late 1980s. “You can freebase it. You can snort it like crack.” Still, he emphasized, “Everything we sell is legal. I don’t want to go to jail for 14 years.”
Mr. Llewellyn is part of a wave of laboratory-adept European entrepreneurs who see gold in the gray zone between legal and illegal drugs. They pose a stiff challenge for European law-enforcement, which is struggling to keep up with all the new concoctions. Last year, 24 new “psychoactive substances” were identified in Europe, almost double the number reported in 2008, according to the Lisbon-based European Monitoring Centre for Drugs and Drug Addiction, or EMCDDA.

Coffee is among the most widely consumed beverages in the world, and that the preponderance of scientific evidence suggests that moderate coffee consumption (3-5 cups per day) may be associated with reduced risk of certain disease conditions, such as Parkinson’s disease. Some research in neuropharamacology suggests that one cup of coffee can halve the risk of Parkinson’s disease. Other studies have found it reduces the risk of Alzheimer’s disease, kidney stones, gallstones, depression and even suicide.