San Pedro cactus

It's not the spikes on these prickly plants you have to watch out for, they also contain mescaline, a strong hallucinogen. San Pedro cacti are increasingly being sold for botanical purposes, but these are more than decorative houseplants. They can give you a high AND make you a basic plant parent, that’s checking a lot of boxes if you ask us. Now that we’ve got you interested, let’s break down the cactus together.

A young woman is sitting at a desktop, reading a textbook. She is learning about the San Pedro Cactus. This is a wide-angle image.

What is the San Pedro cactus (UK)?  

The San Pedro cactus, also known as Trichocereus pachanoi or Trichocereus peruvianus, is an easy-to-grow cactus native to the Peruvian Andes Mountains, where it has been used in rituals for 3000 years. Contrary to popular belief, the cactus doesn’t get its name because it can only grow in San Pedro, which isn’t even a place in South America, but instead from Saint Peter. People believe that the plant allows you to reach the gates of heaven, which Saint Peter has the keys to – pretty smart, right? 

In reality, people feel like they’ve reached ‘the promised land’ because it’s a psychedelic cactus. It contains mescaline which is a strong hallucinogen. The cacti is usually dried and cut into edible ‘buttons’. People then consume san pedro to induce a trip similar to LSD.

What are the effects of the San Pedro cactus?

This dark green mescaline cactus can really trip you out, here’s what to expect: 

  • It can create a dream-like stance with visions and distortions of sound and scale.
  • The experience is similar to LSD, but longer lasting and more physical.
  • The trip can last up to 12 hours and the user is usually in a deep trance, completely detached from the world throughout it.

What are the risks? 

Risks are a given with any substance. We can’t tell you for certain what you’ll go through, but here are some of the nasty side-effects:

  • It’s common to vomit shortly after ingesting the San Pedro cactus.
  • As with any psychedelic substance, it can trigger underlying mental health problems.
  • Hallucinogens can induce upsetting and frightening experiences which you just have to ride out.

The San Pedro cactus (UK) and the law 

Mescaline is illegal in the UK and is listed as a class A drug. However, San Pedro cacti can be bought and sold legally if not intended for human consumption. Legal high providers usually write “not for human consumption” on the packet as a way of dodging the law. But beware of shady drug dealers and read our article to find out how to deal with them.

Top tip: Don’t trust anything, always double and triple check your purchases – whoever they’re from. 

If you’re planning on taking San Pedro cactus: 

  • As with any hallucinogenic, take it in an environment where you feel safe to diminish the chances of having a bad trip.
  • Avoid taking it if you have any mental health issues or a history of mental illness in your family.
  • Make sure you have someone around who can help out if anything goes wrong. And if you’re the designated sober friend, have a look at our article on Drugs First Aid to be prepared.

Next Steps

  • FRANK offers friendly, confidential advice on all things drugs-related. Call now on 0300 123 6600
  • Chat about this subject on our Discussion Boards.
  • Need help but confused where to go locally? Download our StepFinder iPhone app to find local support services quickly.

By Nishika Melwani

Updated on 02-Sep-2021