- Calagula, calagualine, ferns, Polypodiaceae (family), Polypodium cambricum, Polypodium decumanum, Polypodium vulgare, samambaia.
- Extracts of fern species (family Polypodiaceae) have been used traditionally for numerous indications, most commonly in South America and Europe.
- The South American species Polypodium leucotomos L. is commonly known as “calaguala.” Extracts of this species, called “anapsos,” have been marketed and used as a treatment for multiple indications. Although laboratory and animal studies have reported anti-inflammatory, cytokine-suppressing, and leukotriene inhibitory properties, the small number of available human trials have not demonstrated efficacy for any specific indication.
These uses have been tested in humans or animals. Safety and effectiveness have not always been proven. Some of these conditions are potentially serious, and should be evaluated by a qualified healthcare provider.
Laboratory and animal studies report that Polypodium leucotomos extract (anapsos) may reduce inflammation. However, there is little information about the effectiveness of anapsos taken by mouth in people with atopic dermatitis.
Limited scientific information is available about the effectiveness of polypodium in the treatment of dementia.
Extracts of Polypodium leucotomos (called “anapsos”) have been taken by mouth in Europe and South America for psoriasis since the 1970s. Poor-quality human studies report that anapsos may improve skin appearance. However, there is currently little information supporting the use of Polypodium leucotomos for psoriasis. More research is needed in this area before a recommendation can be made.
Early study shows that polypodium may help to prevent sunburn, skin aging, and skin cancers resulting from uncontrolled overexposure of human skin to solar UV radiation (UVA and UVB). Further research is needed to confirm these results.
A combination of polypodium and narrow-band UVB (NB-UVB) light therapy may help treat vitiligo, especially on the head and neck. Additional research is needed in this area.
*Key to grades:
The below uses are based on tradition, scientific theories, or limited research. 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 healthcare provider. There may be other proposed uses that are not listed below.
Adults (18 years and older)
- For psoriasis, a dose of 120 milligrams of anapsos (Polypodium leucotomos extract), taken daily by mouth, has been used for short periods of time in limited research. For UV radiation, 7.5 milligrams per kilogram has been studied. For dementia, preliminary research reports using 360 milligrams daily for four weeks. Safety and effectiveness are not clear.
- No clear topical (on the skin) dosing regimen has been reported or established.
- For vitiligo, 250 milligrams of Polypodium leucotomos has been taken three times daily in combination with narrow-band UVB (NB-UVB) twice weekly for 25-26 weeks.
Children (younger than 18 years)
- Little information is available about the use of polypodium in children and safety is not clear.
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.
- People with allergies to ferns (family Polypodiaceae) should avoid polypodium.
Side Effects and Warnings
- Isolated reports of itching or stomach upset are published. Studies of a different fern species, Polypodium vulgare, report sedation, changes in heart function in animals, low blood pressure, and rapid heart rate. Avoid driving and use of heavy machinery when taking Polypodium leucotomos extract due to theoretical sedative effects. People with heart disease or those being treated for heart disorders or high blood pressure should use caution.
Pregnancy and Breastfeeding
- The use of polypodium during pregnancy or breastfeeding is not recommended because there is little information about its 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.
Interactions with Drugs
- Polypodium may increase the amount of drowsiness caused by some drugs. Examples include benzodiazepines such as lorazepam (AtivanÂ®) or diazepam (ValiumÂ®), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.
- Most testing has been done with a related fern species, Polypodium vulgare. Animal studies show that this related plant can affect the function of the heart and lower blood pressure. In theory, the use of Polypodium leucotomos extract with medications that affect heart function or lower blood pressure may cause the effects of these drugs to increase. Use caution if combining polypodium with heart medications such as beta-blockers, calcium channel blockers, or digoxin.
Interactions with Herbs and Dietary Supplements
- In theory, polypodium may increase the amount of drowsiness caused by some herbs or supplements.
- In studies of a related fern species, Polypodium vulgare, animals treated with the herb developed low blood pressure and changes in heart function. In theory, the use of Polypodium leucotomos extract with herbs or supplements that lower blood pressure may cause the blood pressure to fall too low.
- For the same reason, be cautious if using Polypodium leucotomos extract with herbs or supplements that have possible cardiac glycoside ingredients that can affect the function of the heart. Notably, bufalin/chan suis is a Chinese herbal formula that has been reported as toxic or fatal when taken with cardiac glycosides.
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.
- This information is based on a systematic review of scientific literature edited and peer-reviewed by contributors to the Natural Standard Research Collaboration ().
- Alcaraz MV, Pathak MA, Rius F, et al. An extract of Polypodium leucotomos appears to minimize certain photoaging changes in a hairless albino mouse animal model. A pilot study. Photodermatol Photoimmunol Photomed 1999 Jun-Aug;15(3-4):120-6.
- Alonso-Lebrero JL, Dominguez-Jimenez C, Tejedor R, et al. Photoprotective properties of a hydrophilic extract of the fern Polypodium leucotomos on human skin cells. J Photochem Photobiol B 2003 Apr;70(1):31-7.
- Alvarez XA, Franco-Maside A, Zas R, et al. Anapsos reverses interleukin-1 beta overexpression and behavioral deficits in nbM-lesioned rats. Methods Find Exp Clin Pharmacol 1997 Jun;19(5):299-309.
- Bernd A, Ramirez-Bosca A, Huber H, et al. In vitro studies on the immunomodulating effects of polypodium leucotomos extract on human leukocyte fractions. Arzneimittelforschung 1995 Aug;45(8):901-4.
- Dea-Ayuela M, Rodero M, Rodriguez-Bueno R, et al. Modulation by Anapsos (Polypodium leucotomos extract) of the antibody responses against the nematode parasite Trichinella spiralis. Phytother Res 1999 Nov;13(7):566-70.
- Fernandez-Novoa L, Alvarez XA, Sempere JM, et al. Effects of anapsos on the activity of the enzyme Cu-Zn-superoxide dismutase in an animal model of neuronal degeneration. Methods Find Exp Clin Pharmacol 1997 Mar;19(2):99-106.
- Gomes AJ, Lunardi CN, Gonzalez S, et al. The antioxidant action of Polypodium leucotomos extract and kojic acid: reactions with reactive oxygen species. Braz J Med Biol Res 2001 Nov;34(11):1487-94.
- Gonzalez S, Alcaraz MV, Cuevas J, et al. An extract of the fern Polypodium leucotomos (Difur) modulates Th1/Th2 cytokines balance in vitro and appears to exhibit anti-angiogenic activities in vivo: pathogenic relationships and therapeutic implications. Anticancer Res 2000 May-Jun;20(3A):1567-75.
- Gonzalez S, Pathak MA, Cuevas J, et al. Topical or oral administration with an extract of Polypodium leucotomos prevents acute sunburn and psoralen-induced phototoxic reactions as well as depletion of Langerhans cells in human skin. Photodermatol Photoimmunol Photomed 1997 Feb-Apr;13(1-2):50-60.
- Gonzalez S, Pathak MA. Inhibition of ultraviolet-induced formation of reactive oxygen species, lipid peroxidation, erythema and skin photosensitization by polypodium leucotomos. Photodermatol Photoimmunol Photomed 1996 Apr;12(2):45-56.
- Martinez-Fernandez AR, Nogal-Ruiz JJ, Lopez-Aban J, et al. Vaccination of mice and sheep with Fh12 FABP from Fasciola hepatica using the new adjuvant/immunomodulator system ADAD. Vet Parasitol 2004 Dec 15;126(3):287-98.
- Middelkamp-Hup MA, Bos JD, Rius-Diaz F, et al. Treatment of vitiligo vulgaris with narrow-band UVB and oral Polypodium leucotomos extract: a randomized double-blind placebo-controlled study. J Eur Acad Dermatol Venereol 2007 Aug;21(7):942-50.
- Middelkamp-Hup MA, Pathak MA, Parrado C, et al. Oral Polypodium leucotomos extract decreases ultraviolet-induced damage of human skin. J Am Acad Dermatol 2004 Dec;51(6):910-8.
- Middelkamp-Hup MA, Pathak MA, Parrado C, et al. Orally administered Polypodium leucotomos extract decreases psoralen-UVA-induced phototoxicity, pigmentation, and damage of human skin. J Am Acad Dermatol 2004 Jan;50(1):41-9.
- Navarro-Blasco FJ, Sempere JM. Modification of the inflammatory activity of psoriatic arthritis in patients treated with extract of Polipodium leucotomos (Anapsos) Br J Rheumatol 1998 Aug;37(8):912.
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 . Selected references are listed below.