Pao Pereira (Geissospermum vellosii): Benefits, Dosage, Safety & Evidence

Frequently asked questions

How does Pao Pereira work against cancer cells?

Pao Pereira contains indole alkaloids, particularly flavopereirine, which research suggests may inhibit cancer cell proliferation through multiple pathways. Studies indicate these compounds can induce apoptosis (programmed cell death) and cause cell cycle arrest in cancer cells. The extract appears to selectively target abnormal cells while sparing healthy ones. However, the exact mechanisms remain under investigation, and current evidence is preliminary (Level C), requiring further clinical validation.

Can I take Pao Pereira with chemotherapy drugs?

Pao Pereira should not be combined with chemotherapy without oncologist supervision. While some preliminary research explores complementary use, the safety and potential interactions with specific chemotherapy agents have not been thoroughly studied. The herb could theoretically interfere with treatment efficacy or compound side effects. Patients undergoing cancer treatment must disclose all supplements to their oncologist before adding Pao Pereira to their regimen.

What is the standard dosage of Pao Pereira bark extract?

Research studies have used approximately 350mg of Pao Pereira bark extract taken three times daily for adults. However, this dosing comes from limited preliminary research, not established clinical guidelines. Appropriate dosage may vary based on product concentration, formulation, and individual health factors. Consult a qualified healthcare provider for personalized dosing recommendations, particularly when addressing serious health conditions.

Is Pao Pereira safe to take during pregnancy?

Pao Pereira is contraindicated during pregnancy and should be strictly avoided. The bark contains alkaloids that may stimulate uterine contractions and potentially harm fetal development. Traditional use includes inducing menstruation, suggesting effects on reproductive function. Women who are pregnant, nursing, or attempting to conceive should not use this herb. No safety data exists for use during breastfeeding, so avoidance is recommended.

What are the side effects of Pao Pereira?

Reported side effects of Pao Pereira are generally mild and may include gastrointestinal upset, nausea, and headache. These effects typically occur at higher doses. The herb contains potent alkaloids that can cause adverse reactions in sensitive individuals. Start with lower doses to assess tolerance. Discontinue use if significant digestive disturbances or neurological symptoms occur, and consult a healthcare provider.

PubMed-compiled information sheet

This sheet was compiled from PubMed (NIH) abstracts using AI assistance. Every factual claim is cited to a real PubMed article (see the source list). It has not yet been human-reviewed — confirm with a healthcare provider before use.

Compiled from 30 PubMed articles · model: gemma4:31b

Summary

Pao Pereira (Geissospermum vellosii) is an Amazonian rainforest tree whose bark extracts demonstrate antinociceptive, anticholinesterase, and anticancer properties [PMID:19497357, 19463267, 24033267].

Background

Pao Pereira (Geissospermum vellosii) is a tree widely found throughout the Amazonic forest [PMID:19497357].

Traditional uses

It has been traditionally used by native populations of northern South America to treat malaria [PMID:22143154] and painful disorders [PMID:19497357]. It is also used by oncologic patients and Integrative Medicine practitioners in South America [PMID:24033267].

Active compounds

The stem bark is rich in indole alkaloids [PMID:26840005, 35665643]. Specific identified compounds include geissospermine [PMID:19463267, 32920358], flavopereirine (a beta-carboline alkaloid) [PMID:30795632, 31336690], and 12-metoxy-1-methyl-aspidospermidine [PMID:19497357]. Other isolated alkaloids include geissoschizoline, geissoschizone, and 3',4',5',6'-tetradehydrogeissospermine [PMID:32920358].

Mechanism of action

Pao Pereira extract inhibits 5α-reductase to attenuate benign prostatic hyperplasia [PMID:31873149] and suppresses inflammation-associated NFκB signaling [PMID:32416730, 24287876]. It exhibits anticholinesterase activity by inhibiting acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) [PMID:19463267, 32920358]. Antinociceptive effects are mediated via the 5-HT(1A) receptor [PMID:19497357]. In cancer cells, it may suppress the Wnt/β-catenin signaling pathway [PMID:36178054, 29985062] and, in the case of flavopereirine, downregulate JAKs-STATs and c-Myc signaling [PMID:31336690].

Clinical evidence

Evidence DBenign Prostatic Hyperplasia (BPH)

Reduced prostate weight, proliferative index, and expression of AR, SRD5A1, and PSA in rat models [PMID:31873149]; inhibited viability and induced apoptosis in human BPH cells [PMID:32416730].

Evidence DProstate Cancer

Suppressed growth and induced apoptosis in LNCaP cells and suppressed tumor growth by up to 80% in xenograft mice [PMID:19476740]; suppressed growth, survival, and invasion of castration-resistant PC3 cells [PMID:24287876].

Evidence DOvarian Cancer

Potentiated carboplatin effects against ovarian cancer in preclinical models [PMID:24033267] and inhibited ovarian cancer stem cells in vitro [PMID:36178054].

Evidence DPancreatic Cancer

Induced apoptosis in pancreatic cancer cell lines and showed synergistic effects when combined with gemcitabine in vitro and in vivo [PMID:23674070, 29985062].

Evidence DColorectal Cancer

Flavopereirine lowered cellular viability and induced apoptosis and G2/M-phase cell cycle arrest in CRC cells [PMID:31336690].

Evidence D

Safety & adverse effects

In mice, doses of 60 mg/kg of stembark extract did not result in noticeable cholinergic side effects, but a dose of 200 mg/kg caused whole-body convulsions followed by death [PMID:19463267].

Drug interactions

Pao Pereira extract showed a synergistic effect when combined with gemcitabine in pancreatic cancer cells [PMID:23674070] and potentiated the effects of carboplatin against ovarian cancer [PMID:24033267].

Evidence summary

The current evidence is based entirely on preclinical studies (in vitro cell lines and animal models), representing a low overall level of clinical evidence (Level D).

PubMed sources

1.PMID: 35665643 (2022) — Characterization of alkaloids in bark extracts of Geissospermum vellosii by HPLC-UV-diode array-multistage high-resolution mass spectrometry. · Journal of chromatography. B, Analytical technologies in the biomedical and life sciences
2.PMID: 31873149 (2019) — Pao Pereira Extract Attenuates Testosterone-Induced Benign Prostatic Hyperplasia in Rats by inhibiting 5α-Reductase. · Scientific reports
3.PMID: 24033267 (2014) — The plant extract of Pao pereira potentiates carboplatin effects against ovarian cancer. · Pharmaceutical biology
4.PMID: 39113866 (2024) — Flavopereirine exerts anti-cancer activities in various human thyroid cancer cells. · American journal of cancer research
5.PMID: 19497357 (2009) — Evidence for a role of 5-HT(1A) receptor on antinociceptive action from Geissospermum vellosii.

Pao Pereira

Sources & Citations

Calculate a safe dose of Pao Pereira