Two trials gave mulungu to people about to have wisdom teeth pulled. In 30 people, it beat placebo. In 200 people, it didn’t.
Neither trial tested sleep, which is what most people buy it for.
Mulungu (Erythrina mulungu, also sold as Erythrina verna) is a Brazilian tree whose bark is sold as a calming tea, capsule and tincture. Rodent results look good. Lab work points to nicotinic receptors, and the GABA link is unsettled. In people, the evidence is those two split trials. I found no human sleep trial, no daily-use trial and no human safety trial.
What is mulungu?
A legume tree native to Brazil, 10 to 14 m tall, with red-orange flowers and red-and-black seeds. People brew the bark. The seeds are toxic, so never eat them.
On paper, Brazil takes it seriously. It sits on RENISUS, the Ministry of Health’s 2009 list of 71 medicinal plants of interest, and has a bark monograph in the Brazilian Pharmacopoeia. Yet the Ministry’s 2023 monograph found no valid Anvisa registration for any medicine containing it.
Which plant is in the bag?
Several species are sold as “mulungu” and used the same way. Sources even disagree on whether E. verna and E. mulungu are one species or two.
| Species | Where it grows | Note |
|---|---|---|
| E. mulungu | Southeast, South and Center-West Brazil | Most isolated-alkaloid work used its flowers |
| E. verna | Atlantic rainforest, Bahia to São Paulo | May be the same species as E. mulungu |
| E. velutina | Semiarid Northeast Brazil | By far the most studied |
| E. speciosa | Southeast and South Brazil | A leaf extract showed no anxiety-type effect in rodents |
A label that says only “mulungu” tells you neither the species nor the alkaloid content. When one Brazilian research group checked online sellers, they listed only the common name.
Does mulungu work? The evidence, tier by tier
Nobody knows yet. The closer the evidence gets to people, the thinner it gets.
- 1
Human trialsSplit
Two single-dose dental trials with opposite results. No sleep or daily-use trial.
- 2
Animal studiesPositive in rodents
Calming, anti-seizure and pain effects. Often flower extracts, often injected.
- 3
Cell studiesLab only
Flower alkaloids block nicotinic receptors, mostly the α4β2 type.
- 4
TraditionLong record
Bark tea for nerves, agitation and insomnia in Brazil. Listed as a sedative in several Brazilian pharmacopoeia editions.
- 5
User reportsMixed
Some feel calm, some feel nothing, some feel wired.
Tier 1 is the only one that tested people. It is also the weakest.
The two dental trials, side by side
Trial 1 · Silveira-Souto et al., 2014
30 people
Preferred over placeboHigher preference for mulungu (p = 0.0062). No change in blood pressure, heart rate or oxygen.- Design
- Double-blind crossover
- Dose
- 500 mg capsule, 1 hour before surgery
- Compared with
- Placebo
- Side effects
- Drowsiness only
- Limits
- Small, mostly women
Trial 2 · da Cunha et al.
200 people
No better than placeboPassionflower matched the sedative midazolam. Mulungu did not control anxiety better than a dummy pill.- Design
- Triple-blind, placebo-controlled
- Dose
- Single dose, 60 minutes before surgery
- Compared with
- Placebo, passionflower, midazolam
- Limits
- One dose, surgical setting
The bigger trial is the harder test. Both used one dose, so neither tells you what a week of tea does.
A third trial gave 96 people with mild anxiety a passionflower, hawthorn and mulungu blend and compared it with another herbal mix. Neither won, and there was no placebo arm, so mulungu’s part can’t be separated. The Ministry’s 2023 monograph says efficacy has not been shown in any clinical study.
The animal studies
Rodent work is where mulungu looks best:
- Rats given a flower extract by mouth (200 mg/kg) behaved like rats given diazepam in a maze test.
- Mice given isolated alkaloids at 3 and 10 mg/kg spent more time in the lit half of a light-dark box.
- Alkaloids injected into rat brains blocked seizures, up to 100% in some models.
- A flower extract showed no antidepressant effect.
Most of these used flowers, injections or isolated alkaloids. A mug of bark tea is none of those, and mg/kg in a mouse doesn’t convert cleanly to a person.
Is mulungu a natural Valium?
No. Three reasons:
- The diazepam comparisons are rodent maze scores. A similar score isn’t the same drug.
- In the 200-person trial, mulungu didn’t beat placebo.
- In one rodent study, E. velutina bark impaired memory at low doses but not at higher ones. Benzodiazepines don’t behave that way.
What it may do instead: in cultured cells, two flower alkaloids (erythravine and 11-α-hydroxyerythravine) blocked α4β2 nicotinic receptors at 13 nM and 4 nM (PLoS ONE, 2013). A GABA link has been suggested since 2002 but is unsettled. One alkaloid, erysotrine, blocked seizures in rats without changing GABA binding.
The nicotinic action is why people ask about quitting smoking. So far that’s a hypothesis from cells and animals.
One more gap: those alkaloids came from flowers. The bark has alkaloids too, but no method exists to measure them in the bark drug. The studies and your capsule may not match.
What do people report?
Forum reports split the same way the trials did. They show what people try, not what works.
| Source | What people said |
|---|---|
| Drugs-Forum, 2016 | Shredded bark is hard to strain. One user said 10 g kept them awake through a work day. “Works for some, nothing for others.” |
| Nature’s Herb Forum, 2012 | Felt the tea within minutes. Deep relaxation, no urge to use it daily. |
| Erowid, 2016 | Heaping teaspoon of powder in hot water. Asleep within 30 minutes, weaker nicotine cravings. |
| Bluelight | Long debate about paralysis. One user found it more stimulating than sedating. |
| Social Anxiety Support, 2016 | Kava felt more euphoric. Mulungu was “straight relaxation.” |
How much do people take?
Reported amounts run from a 500 mg capsule to about 18 g of bark a day, a 36-fold spread. None of it is a prescription.
500 mgOne capsule, once. The dental trials.
1–2 g/dayInner bark tincture. Older Brazilian pharmacopoeia text.
12 g/dayRoot bark powder. Brazilian monograph volume.
8–18 g/day4–6 g bark per cup, 2–3 cups. Revoked Brazilian rule, max 3 days in a row.
10–15 gBark steeped at once. Forum users, anecdote only.
0 g6 g12 g18 g
Dark bar: tested in people. Light bars: reference texts. Striped: anecdote.
The Brazilian rule (RDC 10/2010) is revoked, and it capped tea at 3 days in a row. The 30-day limit on some vendor pages has no source behind it. No source sets a safe upper limit. If you take other medicines, ask a pharmacist before any dose.
Tea, powder, tincture or capsule?
No study compares forms.
| Form | Good for | Watch out |
|---|---|---|
| Tea | Matches traditional use | Bitter. Shredded bark is hard to strain. |
| Powder | Cheap, easy to adjust | No alkaloid standard. Easy to over-measure. |
| Tincture | Easier than tea, per one herb book | Strength varies by maker. Contains alcohol. |
| Capsule | The form used in the human trials | Check species, plant part and mg per capsule. |
Is mulungu safe?
Not medical advice. Last reviewed 4 October 2026. The safety record is mostly rodents and tradition. I found no human safety trial of mulungu alone.
Skip mulungu if you
- Are pregnant or breastfeeding.In pregnant rats, 1.5 g/kg of bark extract raised post-implantation loss. No human data outweighs it.
- Have heart failure or a heart rhythm problem.A Brazilian herbal reference advises against Erythrina preparations.
- Take blood pressure drugs or run low.Animal work shows blood-pressure lowering.
- Take sedatives or other psychotropic drugs, unless a pharmacist clears it.Diazepam-type drugs, antihistamines, beta blockers and diabetes drugs are flagged too. None were formally tested.
- Are thinking of the seeds.Erythrina seeds contain toxic alkaloids. Some have been used to numb fish and as rat poison.
Side effects
Drowsiness is the one that shows up in trials. One herb book adds lower blood pressure. No source gives rates, and the Ministry found no adverse-effect data for the bark. Alcohol and antidepressants were never tested with it, so treat mulungu as an added sedative.
Can it paralyze you?
That’s the fear behind the nicotinic story. Related Erythrina alkaloids, such as erythroidine, have curare-like effects in lab animals.
The bark data points the other way. In mice, a bark extract at 200 to 800 mg/kg didn’t affect coordination, and 5 g/kg by mouth killed none over 14 days. The 30-person trial saw no motor problems. The sources contain no human case of paralysis, and no human safety trial either.
What about long-term use?
There’s no human data on long-term use or dependence. In rats, 2.5 g/kg of bark daily for 30 days slightly lowered activity. Leaf and flower extracts raised a DNA-damage marker in mice; bark wasn’t tested. If a page says “not addictive,” ask for its source. I couldn’t find one.
Mulungu vs kava and passionflower
Passionflower has the better human evidence. Kava has a liver warning. Mulungu has neither a clear win nor a clear loss.
| Herb | Human evidence | Main caution |
|---|---|---|
| Passionflower | Matched midazolam in the 200-person dental trial. Also trials for anxiety and insomnia. | Sedation. Check the species on the label. |
| Kava | May help anxiety but may need several weeks (NCCIH). Weak for generalized anxiety disorder. | Rare but serious liver injury. Avoid with alcohol and sedatives. |
| Mulungu | Two split dental trials, one blend trial. | Sedation, pregnancy, heart and blood pressure drugs. Long-term safety unknown. |
One popular herb book says mulungu calms as well as kava, “if not better.” No head-to-head human trial backs that.
How do you buy mulungu without guessing?
Buy only if the label shows
- The botanical name.E. mulungu, E. verna or E. velutina, not just “mulungu.”
- The plant part: bark.Never seeds.
- The amount.mg per capsule or grams per bag. No proprietary blends.
- Country of origin.
- Batch tests for heavy metals and pesticides.The Ministry monograph flags both for herbal raw materials.
Skip anything sold as a “natural Valium.” Labels like “wild crafted” or “fine powder” tell you nothing about alkaloid content.
If stress is the real problem, start with a structured plan like the 14-Day Cortisol Reset Protocol.
Keep reading
References
Primary papers
- Setti-Perdigão P, et al. Erythrina mulungu alkaloids are potent inhibitors of neuronal nicotinic receptor currents in mammalian cells. PLoS ONE 2013;8(12):e82726. doi:10.1371/journal.pone.0082726
- Silveira-Souto ML, et al. Effect of Erythrina mulungu on anxiety during extraction of third molars. Med Oral Patol Oral Cir Bucal 2014. PMC4192578. ClinicalTrials.gov NCT01948622.
- da Cunha RS, et al. Herbal medicines as anxiolytics prior to third molar surgical extraction: a randomized controlled clinical trial. Clin Oral Investig. PMID 32951121
- Fiss E, et al. Passiflora, Crataegus and Erythrina combination efficacy and tolerability compared to Passiflora, Crataegus and Salix in insomnia and mild anxiety. Rev Bras Med 2006;63(9):489-496.
Reviews and official documents
- Brazil Ministry of Health. Informações Sistematizadas da Relação Nacional de Plantas Medicinais de Interesse ao SUS: Erythrina mulungu Mart. ex Benth., Fabaceae (Mulungu). Brasília, 2023. ISBN 978-65-5993-462-1. Cites Onusic 2002 and 2003, Flausino 2007, Faggion 2011, Rosa 2012, Vasconcelos 2003 to 2007, Ribeiro 2006, Proença 2012, De Bona 2012 and De Mello 2007.
- Gilbert B, Alves LF, Favoreto RF. Monografias de Plantas Medicinais Brasileiras e Aclimatadas, Volume II. Rio de Janeiro: Abifisa/Fiocruz, 2022. Entry: Erythrina spp. (Mulungu), pp. 121-140. doi:10.7476/9786557081778
- Silva-Mann R, Rabbani ARC, Gomes LJ, eds. Pensando a Biodiversidade: Mulungu (Erythrina sp.). Instituto Federal da Bahia. Chapters on phytochemistry and pharmacology, ethnobotany and academic publications.
- The Healing Power of Rainforest Herbs. Entry: Mulungu, pp. 363-366, plus remedy and use tables.
- NCCIH. Kava. Updated April 2025. nccih.nih.gov/health/kava