Related Terms

• Iridoid glycosides, isoverbascoside, lamalbid, martynoside, mussaenoside, Pedicularis artselaeri, Pedicularis axillaris Franch., Pedicularis cephalantha Franch., Pedicularis decora, Pedicularis dichotoma Bonati, Pedicula dicora Franch., Pedicularis gracilis Wall., Pedicularis kansuensis, Pedicularis lasiophrys, Pedicularis likiangensis Franch., Pedicularis longiflora, Pedicularis longiflora Rudolph., Pedicularis longiflora var. tubiformis1, Pedicularis longipes Maxim., Pedicularis muscicola Maxim, Pedicularis nordmanniana, Pedicularis olgae Regel., Pedicularis oxycarpa Franch., Pedicularis rex C.B. Clarke, Pedicularis rhinanthoides Schrenk, Pedicularis siphonantha Don, Pedicularis spicata, Pedicularis striata, Pedicularis striata Pall., Pedicularis tapaoensis Tsoong, Pedicularis tenuisecta Franch., Pedicularis yui Li, phenylpropanoid, Scrophulariaceae (family), shanzhiside methyl ester, verbascoside, wood bettony.

Background

• The genus Pedicularis contains several species referred to as louseworts. The common name was derived from the idea that livestock would get lice from eating the plant.

• Pedicularis plants are found mainly in temperate northern hemisphere climates, although some are also found in South America.

• Although animal studies have indicated that certain chemicals found in the plants may have antiproliferative or antioxidant activity, there is insufficient evidence in humans to support the use of Pedicularis species for any indication.

Scientific Evidence

Tradition/Theory

The below uses are based on tradition or scientific theories. They often have not been thoroughly tested in humans, and safety and effectiveness have not always been proven. Some of these conditions are potentially serious and should be evaluated by a qualified health care professional.

• Antioxidant, cancer, chelating agent, fatigue (muscular), muscle relaxant, sedative, snakebite.

Dosing

The below doses are based on scientific research, publications, traditional use, or expert opinion. Many herbs and supplements have not been thoroughly tested, and safety and effectiveness may not be proven. Brands may be made differently, with variable ingredients, even within the same brand. The below doses may not apply to all products. You should read product labels, and discuss doses with a qualified healthcare provider before starting therapy.

Adults (18 years and older):

• There is no proven safe or effective dose for lousewort in adults.

Children (younger than 18 years):

• There is no proven safe or effective dose for lousewort in children.

Safety

The U.S. Food and Drug Administration does not strictly regulate herbs and supplements. There is no guarantee of strength, purity or safety of products, and effects may vary. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy. Consult a healthcare provider immediately if you experience side effects.

Allergies

• Avoid in individuals with a known allergy or hypersensitivity to Pedicularis species or their constituents. Pedicularis is in the same family as snapdragons (Scrophulariaceae).

Side Effects and Warnings

• There are very few reports available on the adverse effects associated with lousewort. Of the available literature, one in vitro study indicates that the Pedicularis species may have iron chelating activities. Avoid in patients with hematological disorders, such as anemia.

Pregnancy and Breastfeeding

• Lousewort is not recommended in pregnant or breastfeeding women due to a lack of available scientific evidence.

Interactions

Most herbs and supplements have not been thoroughly tested for interactions with other herbs, supplements, drugs, or foods. The interactions listed below are based on reports in scientific publications, laboratory experiments, or traditional use. You should always read product labels. If you have a medical condition, or are taking other drugs, herbs, or supplements, you should speak with a qualified healthcare provider before starting a new therapy.

Interactions with Drugs

• Certain constituents in Pedicularis species may have antiproliferative effects. Patients taking anticancer agents should use lousewort cautiously.

• Although not well studied in humans, various Pedicularis species may have antioxidant activity. Caution is advised when taking lousewort with other agents with antioxidant effects.

• Pedicularis species may have iron chelating activity. Use cautiously in patients taking chelating agents, due to possible additive effects.

Interactions with Herbs and Dietary Supplements

• Certain constituents in Pedicularis species may have antiproliferative effects. Patients taking anticancer agents should use lousewort cautiously.

• Although not well studied in humans, various Pedicularis species may have antioxidant activity. Caution is advised when taking lousewort with other herbs or supplements with antioxidant effects.

• Pedicularis species may have iron chelating activity. Use cautiously in patients taking chelating agents, due to possible additive effects. Also, use cautiously when combining iron supplements with lousewort.

Author Information

• This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

References

Natural Standard developed the above evidence-based information based on a thorough systematic review of the available scientific articles. For comprehensive information about alternative and complementary therapies on the professional level, go to www.naturalstandard.com. Selected references are listed below.

1. Chen RC, Su JH, Yang SM, et al. Effect of isoverbascoside, a phenylpropanoid glycoside antioxidant, on proliferation and differentiation of human gastric cancer cell. Acta Pharmacol.Sin. 2002;23(11):997-1001. View Abstract

2. Jia ZJ, Liu ZM, Wang CZ. Phenylpropanoid and iridoid glycosides from Pedicularis spicata. Phytochemistry 1991;30(11):3745-3747. View Abstract

3. Jia ZJ, Liu ZM, Wang CZ. Phenylpropanoid and iridoid glycosides from Pedicularis lasiophrys. Phytochemistry 1992;31(1):263-266. View Abstract

4. Kang J, Jia Z. [Chemical constituents of Pedicularis muscicola Maxim]. Zhongguo Zhong.Yao Za Zhi. 1997;22(3):167-2. View Abstract

5. Li J, Ge RC, Zheng RL, et al. Antioxidative and chelating activities of phenylpropanoid glycosides from Pedicularis striata. Zhongguo Yao Li Xue.Bao. 1997;18(1):77-80. View Abstract

6. Li J, Zheng RL, Liu ZM, et al. Scavenging effects of phenylpropanoid glycosides on superoxide and its antioxidation effect. Zhongguo Yao Li Xue.Bao. 1992;13(5):427-430. View Abstract

7. Li J, Zheng Y, Zhou H, et al. Differentiation of human gastric adenocarcinoma cell line MGc80-3 induced by verbascoside. Planta Med 1997;63(6):499-502. View Abstract

8. Liao F, Zheng RL, Gao JJ, et al. Retardation of skeletal muscle fatigue by the two phenylpropanoid glycosides: verbascoside and martynoside from Pedicularis plicata maxim. Phytother.Res 1999;13(7):621-623. View Abstract

9. Liu ZM, Jia ZJ. Phenylpropanoid and iridoid glycosides from Pedicularis striata. Phytochemistry 1991;30(4):1341-1344. View Abstract

10. Rui-Chuan C, Jin-Hua S, Gao-Liang O, et al. Induction of differentiation in human hepatocarcinoma cells by isoverbascoside. Planta Med 2002;68(4):370-372. View Abstract

11. Su BN, Zhai JJ, Jia ZJ. New iridoids from Pedicularis artselaeri. J Asian Nat.Prod.Res 1998;1(2):103-109. View Abstract

12. Wang CZ, Jia ZJ. Neolignan Glycosides from Pedicularis longiflora. Planta Med 1997;63(3):241-244. View Abstract

13. Wang P, Kang J, Zheng R, et al. Scavenging effects of phenylpropanoid glycosides from Pedicularis on superoxide anion and hydroxyl radical by the spin trapping method(95)02255-4. Biochem.Pharmacol. 3-8-1996;51(5):687-691. View Abstract

14. Zhang F, Jia Z, Deng Z, et al. In vitro modulation of telomerase activity, telomere length and cell cycle in MKN45 cells by verbascoside. Planta Med 2002;68(2):115-118. View Abstract

15. Zheng RL, Wang PF, Li J, et al. Inhibition of the autoxidation of linoleic acid by phenylpropanoid glycosides from Pedicularis in micelles. Chem Phys.Lipids 1993;65(2):151-154. View Abstract