On September 29, 1982, a spate of deaths began in the Chicago area that would prompt a nationwide panic and a frantic search for a still unconfirmed killer – as well as lasting changes to the pharmaceutical industry.
Early that morning, a young girl in the suburbs named Mary Kellerman woke up with a sore throat and a runny nose and told her parents of her symptoms. They gave their 12-year-old daughter an extra-strength Tylenol, a brand of paracetamol (acetaminophen, if you're American). Across town in Arlington Heights, a 27-year-old postal worker named Adam Janus also took a Tylenol for an unknown complaint. Both died shortly afterward of cyanide poisoning.
Later that day, the family of Adam Janus met at his home following his death – which at that point they believed to be due to a heart attack. Here, his brother and sister-in-law both developed headaches and took Tylenol from Adam's supply. Within two days, both of them were also dead.
Police had not yet made a connection between the Tylenol – manufactured by Johnson & Johnson – and the deaths, and wouldn't before three more people died in similar circumstances over the next few days. By testing vast amounts of the drug from pharmacies across the US, they determined that whoever was tampering with the drug was doing so after the drug had left the manufacturers, and the attack was limited to the Chicago area. They were likely taking capsules off the shelves at pharmacies, injecting the gel capsules with the cyanide before resealing the packages. The tampered bottles smelled of almonds – characteristic of cyanide.
Other than that, the police and FBI had pretty much zero leads. In an act of desperation, the FBI even released the location (via the press) of Mary Kellerman's grave, in the hope that the killer might pay a visit. They never showed.
Johnson & Johnson began receiving letters, generously offering to stop the killings in return for $1 million. Eventually, James W. Lewis was identified as the writer due to fingerprints, found guilty of extortion for the letters, and sentenced to 20 years in prison – but was not prosecuted for the actual murders. It was believed that he had sent the letters – ordering that the ransom be paid to the bank account of a defunct company his wife had formerly worked for – in order to try and frame Frederick Miller McCahey, his wife's old boss. For good measure, Lewis had also allegedly sent a letter to Ronald Reagan, which included a death threat.
The crime remains unsolved to this day, and investigations were complicated by potential copycat poisoners two years later.
However, during the panic and the aftermath, steps were taken to ensure that this wouldn't happen again – and you can probably see the effects of the murders in your medicine cabinet right now.
Johnson & Johnson was praised at the time for their response to the killings. Upon being informed of the murders, they put public safety above profit, ordered an immediate recall of their product, and offered $100,000 for information leading to the arrest of whoever placed potassium cyanide in the Tylenol. Six months later, the company had designed new triple-sealed packaging for medication with a glued-shut box, a foil seal, and a plastic ring around the neck of the bottle that would show users if it had been tampered with beforehand.
They worked with the US Food and Drug Administration to produce tamper-evident features so that consumers could easily see if packaging had been opened. These features, such as blister packs and foil seals, soon became standard in the US and around the world. Johnson & Johnson moved away from capsules towards caplets, which were less easy to contaminate.
The killer was never caught, but they at least had to have a serious rethink about their M.O.