Gentile said he has also seen a rise in people trying to get erectile dysfunction drugs for recreational use. The drugs may be used to ensure an erection or counter the effects of something like alcohol.
"We have people coming in all the time for those drugs who don't need it," he said.
But he noted that papaverine is more likely to cause some of the unintended side effects.
"It can produce an erection that does not go away," he said, explaining that such an erection can destroy erectile tissue and result in permanent erectile dysfunction.
Among papaverine's potential side effects are nausea and abdominal cramping.
Its abuse remains rare, if nonexistent.
"We have not seen it as a drug that is commonly, or even rarely, misused at all," said Conway. "Most of the prescription drugs that are misused by kids are in the form of pills, and they're primarily the opiate analgesics, like Vicodan. OxyContin is another one."
Without more information, it will remain unclear whether Loudon took the drug voluntarily and why it was taken -- whether to achieve an erection or in the mistaken belief that its origins in the poppy plant meant it had similar effects to prescription opiates commonly abused by teenagers.
Novelty, in this case, may have been part of what led to death.
"Over time," said Conway, "historically, when drugs are misused, the street figures out the best mode and dosage for the maximum effect. Kids take drugs for lots of reasons -- there's risk versus rewards scenarios that they run through in their heads. Kids are wired to take risks, they're wired to try things that are new."
Incomplete knowledge and a wiring for risk often prove a deadly combination.
"There are enormous risks when someone misuses a serious pharmaceutical drug," said Conway. "Kids are often unaware of the risks that they put themselves at."
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