Calea zacatechichi, also called dream herb and bitter grass, is a shrub plant that primarily grows in Mexico. It has a long history of use for all kinds of health issues, especially gastrointestinal concerns.

Indigenous groups, including the Chontal Maya, have also used it for improved mental clarity and dream enhancement.

Today, it’s a popular herb among people looking to induce hallucinations or try lucid dreaming.

Here’s what else you need to know about the so-called dream herb.

According to anecdotal reports, this dream herb can have a range of effects on your sleep and the quality of your dreams.

Some reported effects on dreams include:

  • the ability to alter or control your dreams
  • more vivid, memorable, or longer dreams
  • an increase in the dreams you experience and remember
  • a sense of deeper knowledge and understanding of your dreams

In particular, this herb appears to help your dreams follow a more coherent narrative structure, instead of abruptly ending or shifting to new locations. This can make your dreams seem longer and even more realistic.

Calea zacatechichi can also have an impact on your sleep.

People often report:

  • feeling drowsy after taking the herb
  • lighter sleep
  • waking up more frequently and easily

While experts aren’t certain exactly how the herb works, some research suggests it produces these effects by acting on the central nervous system.

So, what happens when you take this dream herb but don’t actually sleep?

For some people, Calea zacatechichi appears to increase mental clarity and boost cognitive abilities, like focus and improved reaction time.

As for the alleged hallucinogenic effect, some people do report intense, dream-like images shortly before falling asleep. But it doesn’t seem to cause full-on hallucinations like acid (LSD).

Calea zacatechichi may also temporarily lower your blood pressure and breathing rate, so you might also feel relaxed, sleepy, calm, or even a bit detached from reality.

There’s not a ton of research around this herb’s uses for dream enhancement or mental clarity, but its other health benefits have a bit more evidence behind them.

Some research, for example, supports its potential benefits as a home remedy for:

Calea zacatechichi may also help reduce fever.

The herb has several other uses in folk medicine, but experts haven’t yet found enough evidence to support these.

Nevertheless, anecdotal reports suggest this herb can help relieve:

Most people who use Calea zacatechichi tend to smoke it in a pipe or rolled cigarette, or brew it into a tea.

However, the herb has a bitter taste. Many people find the tea somewhat unpleasant to drink. Others note the smoke tends to be harsh and hard on the lungs.

If you prefer not to smoke the herb or drink the tea, you can also try putting the leaves into gel capsules.

Though you can also purchase it as an extract, extracts and resins of the herb have a higher potency, so you’ll want to decrease your dose accordingly.

Dosing tips

Speaking of doses, if you’re interested in trying it, it’s best to start with very small amounts, since there aren’t any specific dosing guidelines.

Reports from people who have used the herb suggest between 1 and 3 grams may be an effective, safe dose to start with.

Products purchased online may offer some guidance on doses, but keep in mind these aren’t backed by scientific evidence.

Calea zacatechichi is federally classified as an uncontrolled substance in the United States. It’s not regulated by the Food and Drug Administration (FDA). You can purchase and use it legally if you live in most parts of the United States.

If you live in Louisiana, however, you’re out of luck: The state has banned the herb for consumption because it has the potential to alter your mental state.

You can purchase this herb from many online retailers. Local homeopathic or plant medicine shops may also carry it.

If you do decide to purchase it online, make sure to check the ingredients and product description, as many products contain other herbs as well.

Remember, Calea zacatechichi isn’t regulated by the FDA. If you’re going to use it, make sure you find a reputable supplier to avoid purchasing a contaminated product.

Reach out to suppliers to ask about how they source their herbs and test them for purity. If they can’t give you a clear answer, it’s best to avoid them.

To date, experts haven’t found evidence of any specific interactions between Calea zacatechichi and prescription or over-the-counter medications.

However, this doesn’t mean the herb is safe to use with every medication. It simply means experts have yet to find and document conclusive proof of any specific interactions.

As a general rule, it’s best to check with your healthcare provider before trying any new herb or supplement, especially if you have existing health concerns or take any kind of medication or supplement.

This is especially true if you take:

  • Medications to lower blood sugar. Research looking at its potential benefits for the treatment of diabetes does suggest this herb may lower blood sugar. If you take medications for this purpose, Calea zacatechichi could further lower your blood sugar to unsafe levels.
  • Blood pressure medications. The same goes for blood pressure medications, since using this herb can result in lowered blood pressure.
  • Certain anti-anxiety medications. If you take sedatives, tranquilizers, or any other medications intended to help produce a state of calm or relaxation, you may notice an increased effect when taking Calea zacatechichi.

You may also want to use caution when combining this herb with alcohol or other substances, including marijuana.

There’s some evidence to suggest high doses of Calea zacatechichi can cause nausea or vomiting. Some people also report the taste of the tea is bitter enough to cause nausea and a bad taste in the mouth.

If you decide to smoke it to avoid the taste, you may be left with a cough, sore throat, or breathing problems. Plus, smoking of any kind isn’t great for your lungs.

Finally, though the herb has some potential to lower blood sugar, 2016 research evaluating its use as a treatment for diabetes linked use of the herb to renal cell damage and cell death.

However, study authors noted they lacked enough evidence to explain exactly how Calea zacatechichi worked on cells, and emphasized the need for more research.

You may want to talk to your healthcare provider before using Calea zacatechichi or avoid it altogether if you have existing health concerns, including:

If you’re pregnant or breastfeeding, it’s especially important to talk to your healthcare provider before trying this herb.

An allergic reaction is also a possibility. Calea zacatechichi belongs to the Asteraceae (or Compositae) plant family, so you could have an allergic reaction to this herb if you have allergies to:

  • ragweed
  • daisies
  • chrysanthemums
  • other plants in this family

If you’re interested in lucid dreams, or even just having more vivid dreams you can remember, you’re not alone. Plenty of people want to try experiencing more interesting dreams, or dreams that might offer some insight.

Some people swear by using Calea zacatechichi for this purpose, but it’s important to remember that there’s not a ton of research on this herb. Plus, it’s not regulated by the FDA, so finding a quality product can be tricky.

If you’re interested in trying it, make sure to find a reputable supplier and start with a very small dose. If you have a chronic health condition or take medication, it’s best to loop in your healthcare provider before trying it.

Crystal Raypole has previously worked as a writer and editor for GoodTherapy. Her fields of interest include Asian languages and literature, Japanese translation, cooking, natural sciences, sex positivity, and mental health. In particular, she’s committed to helping decrease stigma around mental health issues.