In a twist on selling snake oil to soothe various ailments, some people have taken to hawking rattlesnake pills instead. Now, the Centers for Disease Control and Prevention (CDC) is warning that there can be a serious health risk from popping these pills, as evidenced by a man in Kansas who was hospitalized with a severe Salmonella infection after taking them.

The case actually happened last year, but the CDC has just released a new report on the incident after tests were done on a different batch of pills found in Texas. The results showed that "the Salmonella found in the sample of rattlesnake pills was closely related genetically to an isolate from a patient in Kansas. This close genetic relationship makes it likely that the Kansas patient became ill from consumption of rattlesnake pills.”

The pills are exactly as they sound, made from dehydrated and mashed up rattlesnakes. Yeah, you read that right. Typically, they can be found in all the likely spots, from alternative medicine stores to stalls at the side of the road.

The pills are often marketed and sold to people suffering from conditions such as cancer or HIV. Yet these are precisely two of the groups most at risk of developing a Salmonella infection from the pills.

According to the CDC, people with suppressed or compromised immune systems, such as those who are HIV positive or receiving chemotherapy, are at an increased risk of being hospitalized or even dying from infections caught from taking the pills. Those at risk also include individuals who may have had an organ transplant, are pregnant, or have a genetic condition.

Rather unsurprisingly considering what they are made from, this is not the first time the pills have been linked to Salmonella. “Reptiles and their meat can carry Salmonella species that cause illness,” the researchers write. “Previous outbreak investigations have identified rattlesnake pills as a source of human Salmonella infections.”

You probably don’t need to be told that the pills are not approved by the Food and Drug Administration, and they do not review them for their safety or effectiveness because they don’t work.

The CDC recommends that “persons choosing to take rattlesnake pills, especially persons at higher risk for severe Salmonella infections, should be aware of the risk for salmonellosis associated with their consumption. Consultation with a licensed health care provider to discuss potential risks and benefits is recommended before taking any supplements.”