Health Care Professional Information
Scientific Name
Phytolacca americana, Phytolacca decandra
Common Name
Poke Root, pocan, red plant
Clinical Summary
Derived from various parts of the plant, including root, leaf, and berry. Patients use this herb to treat rheumatoid arthritis, infections, and cancer (as part of the Hoxsey herbal tonic).
Pokeweed causes significant toxicity following oral or topical administration. Reported adverse effects include nausea, diarrhea, protracted vomiting, hypotension, convulsions, dyspnea, and death.
Purported Uses
- Cancer treatment
- Fungal infections
- Induce vomiting
- Infections
- Mastitis
- Rheumatoid arthritis
- Tonsillitis
Constituents
- Alkaloids: Betanidine, betanine, phytolaccine, prebetanine
- Lectins: Pokeweed mitogen glycoproteins (Pa1-Pa5)
- Saponins: Phytolaccosides (A1, D2, and O), jaligonic acid, phytolaccagenic acid, aesculentic acid
- Other: Isoamericanin A, pokeweed antiviral protein (PAP), alpha-spinasterol, histamine, GABA
(1) (4)
Mechanism of Action
Pokeweed mitogens and glycosidic saponins are known toxins that possess mitogenic and irritant properties (1). Pokeweed antiviral protein (PAP) shows broad antiviral activity in vitro. PAP inhibits replication of herpes simplex, influenza and poliovirus, possibly via inactivation of eukaryotic ribosomes (2). Saponin extracts from pokeweed, chiefly phytolaccagenin, exhibit antiinflammatory activity as demonstrated by carrageenan rat paw edema tests. Pokeweed's histamine and GABA content may have hypotensive effects. PAFP-s, an antifungal peptide extract from pokeweed, displays fungistatic effects against a variety of species in vitro (3).
Warnings
Significant toxicity results from oral and topical administration of pokeweed.
Adverse Reactions
Reported: Nausea, vomiting, stomach cramps, diarrhea, weakness, hematemesis, hypotension, tachycardia.
Toxicity: Prolonged vomiting, bloody diarrhea, dyspnea, muscle spasms, convulsions, death.
(1)
Literature Summary and Critique
No study supports the use of pokeweed for any proposed claim.
References
- Newall C, et al. Herbal Medicines: A Guide for Health-Care Professionals, 1st ed. London: Pharmaceutical Press; 1996.
- Irvin JD. Pokeweed antiviral protein. Pharmacol Ther 1983;21:371-87.
- Shao F, et al. A new antifungal peptide from the seeds of Phytolacca americana: characterization, amino acid sequence and cDNA cloning. Biochim Biophys Acta 1999;1430:262-8.
- Takahashi H, et al. Triterpene glycosides from the cultures of Phytolacca americana. Chem Pharm Bull 2001;49:246-8.
Consumer Information
How It Works
Bottom Line: Because there is no evidence that it works and has toxic effects, pokeweed should NOT be used to treat cancer, infections, inflammation, or any other medical condition.
Pokeweed products are extracts from all parts of the plant: leaves, root, and berries. Pokeweed contains chemicals that are known toxins, but several of its other components have shown biological activity in laboratory experiments. For example, pokeweed antiviral protein (PAP) is able to stop replication of viruses such as herpes simplex, influenza and poliovirus in the test tube, while pokeweed anti-fungal protein (PAFP) does the same to fungi. Certain saponins from pokeweed also reduce inflammation in rats. None of these effects have been seen in the human body. Pokeweed is used in allergy testing because it produces an allergic immune response in many people. However, this should not be confused with stimulating the immune system. There is no proof that pokeweed enhances the body's immune response against infections. Moreover, the toxic effects of pokeweed indicate that any benefits might not be worth the risks of taking this herb.
Purported Uses
- To treat cancer
No scientific evidence supports this use. - To treat fungal infections
Although pokeweed extracts stop fungal growth in the test tube, there is no proof from clinical trials that this effect occurs in humans. No other scientific evidence supports this use. - To induce vomiting
Vomiting is a reported side effect of pokeweed. - To treat infections
Although pokeweed extracts stop growth of certain viruses in the test tube, there is no proof from clinical trials that this effect occurs in humans. No other scientific evidence supports this use. - To reduce inflammation in conditions such as mastitis and rheumatoid arthritis
Although pokeweed extracts reduced inflammation in one experiment in rats, there is no proof from clinical trials that it can treat inflammatory conditions in humans. No other scientific evidence supports this use. - To treat tonsillitis
No scientific evidence supports this use.
Research Evidence
No clinical trials have been performed to test whether pokeweed is safe or effective. On the contrary, there have been several reports of pokeweed causing undesirable side effects when ingested or applied topically to the skin.
Patient Warnings
- Significant toxicity results from taking pokeweed by mouth or applying topically.
Side Effects
- Nausea and vomiting
- Stomach cramps
- Diarrhea
- Weakness
- Vomiting blood
- Low blood pressure
- Tachycardia (fast heart rate)
- Toxicity from high doses or prolonged use of pokeweed can cause protracted vomiting, bloody diarrhea, dyspnea (difficulty breathing), muscle spasms, convulsions, and death.
Last updated: September 27, 2011
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