Every so often the media needs to sound the alarm about a new drug that's corrupting the youth of the nation. In the summer of 1967, that drug was the periwinkle plant. The entire scare was based on one group of teenagers in Florida who experimented with the plant, but still it generated plenty of headlines.
Can smoking periwinkle actually get you high? Probably. Over at erowid.org
there are some reports of people experimenting with it. Though despite the scare of 1967, it never caught on as a popular drug.
Dr. George Dame, a health officer in Manatee County, warned that periwinkle could have all kinds of unpleasant side effects (such as "withering of muscle tissue") because periwinkle is the source of some drugs (vinblastine and vincristine) used in chemotherapy. However, an expert on those drugs disagreed with him. From Newsweek
(June 26, 1967):
A chemist at Eli Lilly & Co. of Indianapolis, where the drugs vincristine and vinblastine were developed, said last week that the perils may not be as great as Dame suspects. Both vincristine and vinblastine, he pointed out, are highly unstable and probably do not get into the smoke of burning periwinkle leaves in an active form. Nonetheless, the chemist was quick to put down the periwinkle cult. "Periwinkle," he said, "like most inedible plants, is toxic. You might get pretty sick to your stomach."
Sydney Morning Herald - Jun 4, 1967