Steven Valdez thought he recognized the woman in the Medellín park. Chatting, the two realized they had matched on the dating platform Tinder. They exchanged numbers and made plans.
On their date last spring, he said the woman suggested that he try a typical Colombian dish — a creamy soup called ajiaco. She carried it from a restaurant counter to their table.
He had two spoonfuls, Mr. Valdez, 31, said. “And that’s the last thing I remember.”
Like scores of visitors to the Colombian city last year, Mr. Valdez, a travel blogger, said he was told at the hospital that he had ingested a powerful, potentially fatal cocktail of sedatives, including a drug called scopolamine.
Scopolamine makes its victims black out, and experts say it can also make them unusually open to suggestion — including agreeing to hand over a wallet or reveal passwords.
American officials are so concerned that they issued a security alert this month about the sedatives and a wave of violent crime targeting visitors to Colombia, especially in the increasingly popular tourist destination of Medellín, a city of 2.6 million in a valley of the Andes Mountains.
The U.S. Embassy, in a previous security alert, describes scopolamine as an “odorless, tasteless, memory-blocking substance used to incapacitate and rob unwary victims” and warns of using dating applications in Colombia or visiting nightclubs and bars.
Colombian officials say many of the incidents involve the city’s sex industry.
“Unfortunately, due to word of mouth, people are identifying that in Medellín there are pretty girls and you can party really hard at a very low cost,” said Carlos Calle, who monitors the tourism industry for the city government. “Criminals are taking advantage of that.”
Since the pandemic, Medellín has also drawn thousands of digital nomads seeking cultural immersion and a cheap Airbnb, and investigators and lawyers say that they, too, are being targeted on mainstream dating platforms like Tinder.
Tinder did not respond to a request for comment.
While deaths are relatively rare, authorities in Medellín said the number of robberies involving scopolamine and other sedatives has risen sharply in recent years, though the exact number is unknown, since many victims do not go to the police.
“There are people who feel too embarrassed because if they file a report, people will know what they were doing,” said Manuel Villa Mejía, the city’s security secretary.
Jorge Wilson Veléz, a forensic criminologist who works with victims and their families, said there were likely hundreds of victims last year.
Perpetrators see the robberies as a tax on tourists whom they view as wealthy and in Colombia to prey on women, Mr. Veléz said. The intent is not to kill anybody, he added. “They call it, ‘giving the guys something to sleep.’”
Last year, Medellín saw 1.4 million foreign visitors, nearly 40 percent of whom were American, according to city data.
Crimes against American visitors have stirred fears in the expat community. An English-language Facebook group, Colombia Scopolamine Victims & Alerts, has about 3,800 members.
Americans are being hit, Mr. Veléz said, because they’re going online “looking for company, a relationship,” and especially when they go on dates alone.
Scopolamine, also known as “devil’s breath,” has been reported elsewhere in Latin America and beyond, with cases popping up from London to Bangkok.
But the drug’s rise in Colombia, and the embassy’s warning to Americans, comes as a particular blow to a country trying hard to change its image.
Medellín, in particular, has struggled to shed associations with drugs, violence and Pablo Escobar. The city has undergone a major transformation since the 1990s, boasting sleek museums, cafes on tree-lined streets, and the country’s only metro system. While some criminal gangs remain, the city’s homicide rates have plunged.
Crimes targeting tourists may tarnish that rosy picture — but so, too, do the tourists themselves, according to officials and lawyers who represent men targeted by thieves, who say some are treating Medellín like a lurid playground.
“There’s this weird mystique. You come to Medellín, and the normal rules don’t apply,” said Alan Gongora, an American lawyer in Medellín. “Like, anything is possible.’’
Some crime victims said they were just looking for a date.
During the pandemic, Mr. Valdez left Los Angeles, where he worked in television production, to travel and work on his blogs, including one called We Like Colombia. He was in Medellín last May, working and taking bachata lessons, he said, when he opened Tinder to find a dance partner.
After his date with a woman who called herself Luisa, he said he woke up in his Airbnb, alone and unable to stand up. His right leg felt broken.
The police later told him his captors had beat him, likely because he had resisted being robbed, Mr. Valdez said. Hospital blood tests revealed the presence of scopolamine and another drug, clonazepam, a depressant.
He lost his phones, laptop, wallet and about $7,000, he said.
But he felt lucky to be alive.
Mr. Valdez reported the attack, and his date and several others were arrested after trying to use his bank cards to purchase appliances at a store, according to the police.
He tries to keep what happened in perspective. “I’ve been to Colombia, like, eight times now since the pandemic,” said Mr. Valdez, who now lives in Puerto Rico. “I’ve seen organized crime is rampant because prices are going so high over there. You know, the regular citizens can’t afford it.”
Criminal groups that lure victims through dating platforms are typically small, unaffiliated crews from poor neighborhoods, investigators in Medellín said.
One 42-year-old man from New York recalled being drugged by a Tinder date who served him a rum and coke that he said knocked him out for 24 hours.
She stole his electronic devices, silver jewelry, a bank card and cash. “I thought I had lost everything,” said the man, who asked to go by his initials, R.J., to protect future job prospects. But his passport and IDs were right where he had hidden them. A police report viewed by The Times corroborated details of the crime.
Leaving a passport, investigators said, is a signature of these crimes — meant to encourage victims to leave without reporting the robbery or pressing charges.
Some thieves can be sophisticated.
In December, a young German scientist touring Latin America and posting videos under the name Dr. Travel said he was robbed in Medellín by a woman he was “chatting with” after joining her and her friend for a meal.
He drank a pink soda, he said in a video, and later awoke to find his wallet and phone gone. His phone’s tracking function was deactivated, his Apple ID password changed and his bank account drained. Holdings in several cryptocurrency exchanges were sold, the funds moved to other crypto wallets.
He lost more than $16,000, he said. Attempts to reach the man were unsuccessful.
Scopolamine has long been used to treat motion sickness and nausea, but became popular in larger doses around three decades ago as a recreational drug and to commit crimes, said Guillermo Castaño, a senior investigator for Colombia’s science ministry.
Around 10 years ago, criminals in Colombia started using it to target tourists, Dr. Castaño said, often mixing it with benzodiazepines, depressants that typically treat insomnia and anxiety, to further incapacitate victims.
In a widely publicized case, Paul Nguyen, a 27-year-old from California, was fatally drugged by a Tinder date in Medellín in late 2022, his body found near a dumpster. An autopsy determined he had been drugged with clonazepam, which, combined with alcohol, had caused his death.
His date and several accomplices were arrested and are now on trial, tracked down with the help of a photo of the woman that Mr. Nguyen posted on Snapchat before he disappeared.
Medellín authorities have said stopping the attacks is a top priority. Four people were recently arrested in connection with the murder of another American tourist who may have met a date online.
Still, arrests are rare.
Mr. Nguyen’s mother, Kimberly Dao, said the family had to hire Mr. Velez, the investigator, to push the police to pursue the case.
For Ms. Dao, the U.S. Embassy alert about online dating in Colombia is a sign the issue is being taken seriously — though she wished it had come sooner.
If it had, she said, “I would beg him, I would not let him go.”
Federico Rios contributed reporting from Medellín, Colombia, and Simon Posada contributed reporting from Bogotá, Colombia.