Picrasma (Picrasma excelsa): Benefits, Dosage, Safety & Evidence

Questions fréquentes

How does Picrasma excelsa work as a digestive tonic?

Picrasma excelsa contains intensely bitter quassinoids, including quassin and neoquassin, which stimulate bitter taste receptors on the tongue. This triggers a vagal reflex that increases gastric acid secretion, bile flow, and digestive enzyme production, enhancing overall digestive function. The same quassinoid compounds also demonstrate antimalarial activity by interfering with parasite protein synthesis. Evidence Level: C (preliminary research and traditional use support these mechanisms).

Is Picrasma safe to take during pregnancy?

No, Picrasma excelsa is contraindicated during pregnancy and should be strictly avoided. The quassinoid compounds have documented emmenagogue properties and may stimulate uterine contractions, posing potential risks to pregnancy. Traditional evidence and available data (Level C) classify it as unsafe for pregnant women. Women who are pregnant, trying to conceive, or breastfeeding should not use Picrasma preparations in any form.

What is the recommended dosage for Picrasma wood tea?

The traditional adult dosage for Picrasma excelsa wood tea is one cup daily, prepared from a very small chip of the dried wood. For tincture preparations, the recommended dose is 1-2ml daily. Due to its extreme bitterness—one of the most bitter substances known—larger amounts may cause toxicity and are not recommended. Start with the smallest effective dose and never exceed recommended amounts. Evidence Level: C (traditional use).

Does Picrasma interact with antimalarial medications?

Limited clinical data exists on specific drug interactions with Picrasma excelsa. Due to its documented antimalarial properties, there is theoretical potential for additive or conflicting effects when combined with conventional antimalarial drugs. The bitter compounds may also affect absorption of oral medications. Patients taking antimalarials or other prescription medications should avoid concurrent use without medical supervision. Evidence Level: C (theoretical based on pharmacological activity).

What are the side effects of taking Picrasma?

The primary side effect of Picrasma excelsa is its extreme bitterness, which frequently causes immediate nausea and taste aversion. Excessive doses can trigger vomiting and have documented toxicity. The wood is so intensely bitter that it has been historically used as a natural insect repellent and denaturant. Other potential effects include gastric irritation. Users should strictly adhere to recommended dosages and discontinue use if severe gastrointestinal symptoms develop. Evidence Level: C.

What conditions is Picrasma traditionally used to treat?

Picrasma excelsa has been traditionally used for malaria treatment and prevention, as a digestive tonic to stimulate appetite in cases of anorexia, and topically for head lice infestations. The antimalarial activity is attributed to quassinoid compounds that interfere with parasite development. While these uses are supported by traditional practice and preliminary research, clinical evidence remains limited (Level C), and conventional treatments should not be replaced without medical guidance.

Fiche d'information compilée à partir de PubMed

Cette fiche a été compilée à partir de résumés PubMed (NIH) avec l'assistance d'une IA. Chaque affirmation factuelle est citée par un article PubMed réel (voir la liste des sources). Elle n'a pas encore été révisée par un humain — confirmez auprès d'un professionnel de santé avant utilisation.

Compilé à partir de 30 articles PubMed · modèle : gemma4:31b

Résumé

Picrasma is a genus of the Simaroubaceae family distributed in Asia and America, utilized in folk medicine for various inflammatory, infectious, and metabolic conditions [PMID:34302942].

Contexte

The genus Picrasma consists of six species found primarily in tropical and subtropical regions of Asia and America [PMID:34302942]. Species such as P. quassioides, P. chinensis, and P. excelsa are noted for their medicinal significance [PMID:34659503, PMID:36691852, PMID:19016402].

Usages traditionnels

Folk medicines from Picrasma species (barks, roots, stems, branches, or leaves) have been used to treat fever, sore throat, dysentery, eczema, nausea, loss of appetite, diabetes mellitus, cancer, and hypertension [PMID:34302942]. P. quassioides specifically has been used for gastric discomfort and pediculosis [PMID:32858812], as well as skin conditions including atopic dermatitis, psoriasis, scabies, and boils [PMID:38789093].

Composés actifs

The genus contains a complex composition of phytochemicals, primarily quassinoids (such as quassin and neoquassin), alkaloids (including β-carbolines, canthinones, and alkaloid dimers), and terpenoids [PMID:34768188, PMID:32858812, PMID:15038116]. Other identified compounds include tirucallane triterpenoids, phenylethanoid derivatives, and cyclopeptide alkaloid-type burpitides [PMID:30530072, PMID:36810976, PMID:38787765].

Mécanisme d'action

Neuroprotective effects are observed via the suppression of cell apoptosis and downregulation of caspase-3 activation [PMID:30917277]. Anticancer activity in oral squamous cell carcinoma involves arresting the cell cycle at the G2/M phase by downregulating cyclin A, cyclin B, CDK4, and CDK6, and inducing apoptosis through the activation of PARP and caspases 3, 8, and 9 [PMID:34894061].

Preuves cliniques

Preuve DNeurodegenerative disorders (Alzheimer's/Parkinson's)

P. quassioides stem extract improved memory and cognitive abilities in amyloid-β peptide-induced AD mice by reducing Aβ1-42 deposition and suppressing neuroinflammation [PMID:31520892]. A compound from P. chinensis (Picrachinentin A) improved motor behavioral performance in MPTP-induced Parkinson's disease animal models [PMID:38787765].

Preuve DRheumatoid Arthritis

Total alkaloid extract from P. quassioides delivered via hyaluronic acid decorated lipid-polymer hybrid nanoparticles showed anti-inflammatory activity in collagen-induced arthritis rats [PMID:37023852].

Preuve DCancer

Picrasidine I from P. quassioides reduced cell viability in oral squamous cell carcinoma cells in a dose-dependent manner [PMID:34894061]. Other compounds from P. chinensis and P. quassioides showed cytotoxicity against HepG2 and MDA-MB-231 cell lines [PMID:38936674, PMID:30530072].

Preuve DInflammation

Phenylethanoid derivatives from P. quassioides leaves exhibited inhibitory effects on NO levels in LPS-induced BV-2 microglial cells [PMID:36810976].

Sécurité et effets indésirables

Total alkaloid extracts from P. quassioides have been noted to have high toxicity (IC50 = 8.088 ± 0.903 μg/ml) [PMID:37023852].

Interactions médicamenteuses

Quassin and neoquassin from P. excelsa (Jamaican bitterwood tea) exhibit potent inhibition of the cytochrome P450 enzyme CYP1A1 [PMID:19016402].

Synthèse des preuves

The current evidence is primarily based on in vitro cell studies and in vivo animal models (Level D), with some comprehensive reviews (Level C) summarizing ethnopharmacological uses. There are no human clinical trials (Level B) or meta-analyses (Level A) provided in the source material.

Sources PubMed

1.PMID: 34302942 (2021) — Genus Picrasma: A comprehensive review on its ethnopharmacology, phytochemistry and bioactivities. · Journal of ethnopharmacology
2.PMID: 12737395 (2003) — Quassinoids from Picrasma crenata. · Natural product research
3.PMID: 34659503 (2021) — Pharmacological effects of Picrasma quassioides (D. Don) Benn for inflammation, cancer and neuroprotection (Review). · Experimental and therapeutic medicine
4.PMID: 15038116 (2003) — [Analysis of constituents in Jamaica quassia extract, a natural bittering agent]. · Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan
5.PMID: 34768188 (2022) — Alkaloids from Picrasma quassioides: An overview of their NMR data, biosynthetic pathways and pharmacological effects. · Phytochemistry

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Sources et citations

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