Picrasma Excelsa
Also known as: Quassia excelsa Sw., Jamaican Quassia, Bitter wood, Amargo, Ruda, Surinam Quassia, Picrasma excelsa
Overview
Picrasma excelsa, commonly known as Jamaican Quassia or Bitter wood, is a tropical tree native to the Caribbean, Central, and Northern South America. Its bark and wood extracts are intensely bitter and have been traditionally used for medicinal purposes and as a flavoring agent in foods and beverages. Historically, it has been employed to reduce fever, stimulate appetite, improve digestion, and treat parasitic infections like lice and worms. The plant contains bioactive phytochemicals, primarily quassinoids, along with β-carbolines and canthinones, which are believed to be responsible for its various pharmacological activities. While traditional uses are well-documented, the scientific research on Picrasma excelsa is moderate, with many studies focusing on phytochemical characterization and in vitro/animal models, and a notable lack of high-quality clinical trials.
Benefits
Picrasma excelsa is traditionally recognized for several benefits, primarily its use in reducing fever, stimulating appetite, and improving digestion. It has also been used as an insecticide and anthelmintic to treat lice and intestinal worms. Preclinical studies and in vitro research indicate that its active compounds, particularly quassinoids, possess anti-inflammatory, antioxidant, antimicrobial, anti-cancer, and anti-parasitic properties. These effects have been observed in various laboratory and animal models, suggesting potential therapeutic applications. In traditional medicine, particularly in Caribbean and Asian regions, it is frequently used for gastrointestinal discomfort and parasitic infestations. However, it is crucial to note that clinical evidence supporting these benefits in humans is largely absent, and most data are derived from traditional usage reports and preclinical studies. The strength of evidence for human benefits is currently low, awaiting rigorous clinical trials.
How it works
The primary mechanism of action for Picrasma excelsa is attributed to its quassinoid compounds. These compounds are known to inhibit cytochrome P450 enzymes, such as CYP1A1, which may modulate drug metabolism and contribute to their pharmacological effects. Quassinoids also exhibit cytotoxic activity against various cancer cells and demonstrate antimicrobial properties, likely by disrupting cellular metabolism and membrane integrity of pathogens. The intense bitter taste of Picrasma excelsa extracts stimulates digestive secretions, thereby improving appetite and aiding digestion. While specific absorption and bioavailability data in humans are limited, quassinoids are known to be bioactive at low concentrations in animal studies, suggesting potent effects even at small doses.
Side effects
Picrasma excelsa is generally considered safe when consumed in traditional doses and as a food additive. However, high doses can lead to adverse effects, primarily gastrointestinal irritation and vomiting due to its intense bitterness and potential for toxicity. Parenteral administration of isolated quassin, one of its active compounds, has been shown to be toxic in animal studies, causing cardiac irregularities and neurological symptoms. It is strictly contraindicated during pregnancy due to documented adverse effects, including reproductive toxicity observed in animal models. While no well-documented drug interactions exist, the inhibition of CYP enzymes by quassinoids suggests a potential for interactions with other medications metabolized by these pathways. Safety in specific populations, such as children and the elderly, has not been adequately studied, and caution is advised. The maximum safe dose is not well-defined, and exceeding traditional doses should be avoided due to the risk of toxicity.
Dosage
Traditional oral doses of quassia wood extract are approximately 500 mg daily, typically consumed as an infusion or decoction. However, this dosage is based on historical use and has not been clinically validated through modern trials. For topical applications, such as tinctures for lice treatment, standardized dosing is not established, and usage is guided by traditional practices. There is no well-defined maximum safe dose, and exceeding traditional amounts can lead to toxicity, including gastrointestinal upset and vomiting. Due to the lack of robust clinical data, specific recommendations regarding timing (e.g., before or after meals) or the optimal form for absorption are not available. Users should exercise caution and adhere to traditional low doses, avoiding prolonged or high-dose use, especially given the potential for reproductive toxicity and other adverse effects at higher concentrations.
FAQs
Is Picrasma excelsa safe for everyone?
It is generally safe at traditional doses, but high doses or parenteral use can be toxic. It is strictly contraindicated during pregnancy due to documented adverse effects.
What are the primary traditional uses of Picrasma excelsa?
Its main traditional uses include reducing fever, stimulating appetite, improving digestion, and treating parasitic infestations like lice and intestinal worms.
Has Picrasma excelsa been studied in clinical trials?
No high-quality randomized controlled trials meeting strict scientific criteria have been published to date, meaning most evidence is preclinical or traditional.
How quickly can one expect to see effects from Picrasma excelsa?
The time course for effects is unknown due to a lack of clinical data; traditional use suggests effects may appear with regular use over days to weeks.
Research Sources
- https://pubmed.ncbi.nlm.nih.gov/32858812/ – This systematic review identified approximately 94 phytochemicals in Picrasma quassioides (a related species), highlighting their anti-inflammatory, antioxidant, antimicrobial, and anticancer activities. The review noted the limited clinical evidence and potential toxicity concerns, emphasizing that most data are preclinical.
- https://www.drugs.com/npp/quassia.html – This clinical overview summarizes the traditional uses, safety profile, and toxicology of Quassia. It highlights the lack of clinical trial evidence for efficacy and provides important warnings, particularly against its use during pregnancy due to documented adverse effects.
- https://www.quasix.eu/pdf/4-2/Data_Quassia_1.pdf – This experimental animal study in rats investigated the effects of Quassia extract on reproductive organs. It found that the extract reduced reproductive organ weights and affected sperm parameters, implicating quassin as the active compound responsible for these reproductive toxicities.
- https://pfaf.org/user/Plant.aspx?LatinName=Picrasma+excelsa – This source provides general information on Picrasma excelsa, including its common names, traditional uses, and basic botanical characteristics. It serves as a reference for the plant's historical and ethnobotanical significance.
- https://tropical.theferns.info/viewtropical.php?id=Picrasma+excelsa – Similar to the PFAF database, this source offers details on the tropical plant Picrasma excelsa, covering its distribution, traditional applications, and general properties. It supports the understanding of its historical use in various regions.
- https://pubmed.ncbi.nlm.nih.gov/19016402/ – This study investigates the effects of quassinoids on cytochrome P450 enzymes. It suggests that quassinoids can inhibit CYP1A1, which may modulate drug metabolism and contribute to the pharmacological effects of Picrasma excelsa, providing insight into its mechanism of action.
