FWD 2 Expanded Commission E: Pumpkin seed

Herbal Medicine: Expanded Commission E

Pumpkin seed

Latin Name: Cucurbita pepo
Pharmacopeial Name: Cucurbitae peponis semen
Other Names: n/a

Overview

Pumpkin is an herbaceous, monoecious, annual vine native to America, now cultivated worldwide in warm and temperate regions (Bombardelli and Morazzoni, 1997; Wichtl and Bisset, 1994). The material of commerce comes mainly from medicinal cultivars (Cucurbitae semen c.v. peponis medicinalis) grown in southeastern Europe, mainly Austria, Hungary, and the former Yugoslavia (BHP, 1996; Wichtl and Bisset, 1994), China, Mexico, and the former U.S.S.R. (Wichtl and Bisset, 1994). Pumpkin has been cultivated in Mexico and North America since at least 14,000 B.C.E. based on archaeological evidence (Bombardelli and Morazzoni, 1997).

Pumpkin seed has been used in traditional medicine as an anthelmintic (an agent used to expel intestinal worms), taeniacide (an agent which kills tapeworms) and as a diuretic (Bombardelli and Morazzoni, 1997). Its modern clinical uses are comparable to its traditional uses in North American aboriginal medicine. For example, the Cherokee people used pumpkin seed as an anthelmintic and also as a pediatric urinary aid to treat bed-wetting. The Iroquois people prepared an infusion of the seeds as a diuretic given to children with reduced urination. The Menominee people of Wisconsin used the seed to facilitate the passage of urine (Moerman, 1998). The seeds have been reported to eliminate both tapeworms and roundworms (Budavari, 1996; Tyler, 1993). An amino acid, curcubitacin, is thought to be responsible for the seed's anthelmintic actions (Tyler, 1993). To use pumpkin seed as an anthelmintic agent, one method of preparation is to pound or grind 200400 g of unpeeled seeds into a pulp, then mix the pulp with milk and honey until reaching a porridge-like consistency. Ingestion on an empty stomach in the morning, in two doses, is recommended, followed by castor oil 23 hours later. Another method is to combine 150 g of unpeeled, crushed pumpkin seeds with senna electuary. An electuary is a preparation made by mixing the drug (e.g., senna) with honey or syrup to form a pasty mass (Weiss, 1988).

Pumpkin seeds are considered an alternative treatment for stage 1 and 2 benign prostatic hyperplasia (BPH). In stage 1 BPH, urination is frequent, and causes numerous interruptions of sleep during the night. There may be a delay in beginning urination, and also post-void dribbling. Stage 2 symptoms indicate bladder function debility, and include urgency and incomplete emptying of the bladder. In addition, Commission E also approves the use of pumpkin seed for the treatment of irritable bladder; the seeds may help to reduce childhood incidence of bladder stones in areas where the condition is endemic. A study in Thailand demonstrated that pumpkin seeds reduced oxalcrystalluria (formation of bladder stones due to the accumulation of oxalate crystals) in boys between the ages of 2 and 7, while increasing pyrophosphate, glycosaminoglycans, and potassium values (Suphakarn et al., 1987).

Countries where men have traditionally consumed pumpkin seeds to reduce prostate enlargement include Bulgaria, Turkey, and the Ukraine (Tyler, 1993; Weiss, 1988), but as with many promising herbal remedies, while efficacy is established empirically, it has not been proven scientifically. Similarly, how pumpkins seeds may or may not work in BPH is not currently known. One theory suggests that the fatty oil content of the seeds, at a 50% concentration, may precipitate diuresis (Tyler, 1993) and may be of benefit not only in prostate hyperplasia but also in irritable bladder. Others postulate that delta-7 sterols in the fatty oils block dihydrotestosterone from androgen receptors, which may prevent the hyperproliferation of prostate cells (Schulz et al., 1998). This theory is somewhat supported by a small, open study in which six patients who were scheduled for radical prostatectomies agreed to take pumpkin seed sterols for three to four days before the operation. When the prostatectomies were performed, tissue removed from the patients taking the sterols contained much less dihydrotestosterone, compared to dihydrotestosterone levels in the tissues taken from the control group (Schilcher, 1992).

Clinical studies on the effects of pumpkin seed preparations in BPH patients are generally lacking. However, in one study, 53 BPH patients participated in a three-month double-blind study. Results showed that urinary flow, frequency, time spent urinating, post-void dribbling and backwash, and subjective feelings about their symptoms significantly improved in the participants given the pumpkin seed preparation (Carbin et al., 1990). The success of this study indicates that follow-up studies are warranted.

In Germany, pumpkin seed is official in the German Pharmacopeia, tenth edition, approved in the Commission E monographs, and also official in the German Standard License monographs (Braun et al., 1997; DAB 10, 19911996; Wichtl and Bisset, 1994). It is used as a component of a few urological and prostate drug preparations (e.g., Prosta Fink N, by Fink and Prostamed, by Klein) (Weiss, 1988; Wichtl and Bisset, 1994). In German pediatric medicine, pumpkin seed preparations (e.g., Granufink K rbis-Granulat, by Fink) are used to treat irritable bladder and also enuresis nocturna (bedwetting). Granufink is a granulated and sugar-coated pumpkin seed from a medicinal cultivar of pumpkin (e.g., Cucurbita pepo L. convar. citrullinina Greb. var. styriaca Greb.) (Schilcher, 1997). In the United States, pumpkin seed was listed in the United States Pharmacopeia fifth through tenth editions (Bombardelli and Morazzoni, 1997).

German pharmacopeial grade pumpkin seed consists of the whole, dried, ripe seed of C. pepo and/or different cultivars of this species. Botanical identification must be confirmed by macroscopic and microscopic examinations plus organoleptic evaluation. It must not smell or taste rancid (DAB 10, 19911996). The British Herbal Pharmacopoeia requirements are comparable to the DAB though it requires an additional identification test by a thin-layer chromatography (TLC) method (BHP, 1996). The German Standard License quantitative standards include not less than 35% diethyl ether-soluble extractive and not less than 0.1% total sterols (Wichtl and Bisset, 1994).

Description

Pumpkin seed consists of the ripe, dried seed of C. pepo L. and cultivated varieties of C. pepo L. [Fam. Cucurbitaceae] and its preparations in effective dosage. The seed contains cucurbitin, phytosterol in free and bound forms, b- and g-tocopherol, and minerals, including selenium.

Chemistry and Pharmacology

Pumpkin seed contains amino acids (e.g., cucurbitin); approximately 1% phytosterols in free and bound forms; squalene; chlorophyll pigments (chlorophyll b and pheophytin a); 45% minerals including selenium, zinc, calcium, copper, iron, manganese, phosphorous, and potassium; approximately 30% pectins; approximately 2551% proteins (Bombardelli and Morazzoni, 1997; Wichtl and Bisset, 1994); approximately 3050% oil, composed mainly of fatty acids including palmitic, stearic, oleic, and linoleic acids; tocopherols (b- and g-tocopherol); carotenoids (lutein and b-carotene). Due to a broad genetic diversity, the oil content of pumpkin seed is highly variable depending on the taxon (Bombardelli and Morazzoni, 1997; Murkovic et al., 1996a; Murkovic et al., 1996b).

The Commission E reported that due to the lack of suitable models, there are not enough pharmacological studies to substantiate the empirically found clinical activity.

The British Herbal Pharmacopoeia reported prostatic action (BHP, 1996). The Merck Index reports its therapeutic category as anthelmintic (Budavari, 1996). The constituents tocopherol and selenium may have a protective function towards the oxidative degradation of lipids, vitamins, hormones, and enzymes. Protein fractions of pumpkin seed are thought to function as trypsin inhibitors (Krishnamoorthi et al., 1990; Wichtl and Bisset, 1994). A recent review of studies on the therapeutic activity concluded that pumpkin seed inhibits 5a-reductase in vitro.In vivo, it has demonstrated anti-androgenic and anti-inflammatory activity (Bombardelli and Morazzoni, 1997).

Uses

The Commission E approved pumpkin seed for irritable bladder and micturition problems of benign prostatic hyperplasia stages 1 and 2.

The German Standard License indicates its use for supportive treatment in functional disorders of the bladder and for difficult urination (Braun et al., 1997). Childhood enuresis nocturna and irritable bladder have been treated successfully with pumpkin seed (Schilcher, 1997). It has also been used to eradicate tapeworm (Weiss, 1998).

Contraindications

None known.

Side Effects

None known.

Use During Pregnancy and Lactation

No restrictions known.

Interactions with Other Drugs

None known.

Dosage and Administration

Unless otherwise prescribed: 10 g per day of whole and coarsely ground seed and other galenical preparations for internal uses.

Seed: 10 g coarsely ground or well chewed seed taken with fluid (Commission E).

The German Standard License lists a higher dosage: 1-2 heaping tablespoons (15-30 g) coarsely ground or well chewed seed, taken with fluids, in the morning and evening. It is recommended to remove the testa (outer covering) from hard seeds beforehand (Braun et al., 1997).

Note: This medication relieves only the symptoms associated with an enlarged prostate without reducing the enlargement. Please consult a physician at regular intervals (Commission E).

References

British Herbal Pharmacopoeia (BHP). 1996. Exeter, U.K.: British Herbal Medicine Association.

Bombardelli, E. and P. Morazzoni. 1997. Curcubita pepo L. Fitoterapia 68(4).

Braun, R. et al. 1997. Standardzulassungen f r FertigarzneimittelText and Kommentar. Stuttgart: Deutscher Apotheker Verlag.

Budavari, S. (ed.). 1996. The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals, 12th ed. Whitehouse Station, N.J.: Merck & Co, Inc.

Carbin, B.E., B. Larsson, O. Lindahl. 1990. Treatment of benign prostatic hyperplasia with phytosterols. Br J Urol 66(6):639641.

Deutsches Arzneibuch, 10th ed. (DAB 10). 19911996. (With subsequent supplements through 1996.) Stuttgart: Deutscher Apotheker Verlag.

Krishnamoorthi, R., Y.X. Gong, M. Richardson. 1990. A new protein inhibitor of trypsin and activated Hageman factor from pumpkin (Cucurbita maxima) seeds. FEBS Lett 273(12):163167.

Moerman, D.E. 1998. Native American Ethnobotany. Portland, OR: Timber Press, Inc.

Murkovic, M., A. Hillebrand, J. Winkler, W. Pfannhauser. 1996a. Variability of vitamin E content in pumpkin seeds (Cucurbita pepo L.). Z Lebensm Unters Forsch 202(4):275278.

Murkovic, M., A. Hillebrand, J. Winkler, E. Leitner, W. Pfannhauser. 1996b. Variability of fatty acid content in pumpkin seeds (Cucurbita pepo L.). Z Lebensm Unters Forsch 203(3):216219.

Schilcher, H. 1997. Phytotherapy in Paediatrics: Handbook for Physicians and Pharmacists. Stuttgart: Medpharm Scientific Publishers.

. 1992. Phytotherapie in der Uroligie. Stuttgart: Hippokrates Verlag.

Schulz, V., R. Hnsel, V.E. Tyler. 1998. Rational Phytotherapy: A Physicians' Guide to Herbal Medicine. New York: Springer.

Suphakarn, V.S., C. Yarnnon, P. Ngunboonsri. 1987. The effect of pumpkin seeds on oxalcrystalluria and urinary compositions of children in hyperendemic area. Am J Clin Nutr 45(1):115121.

Tyler, V. 1993. The Honest Herbal: A Sensible Guide to the Use of Herbs and Related Remedies, 3rd ed. New York: Pharmaceutical Products Press.

Weiss, R.F. 1988. Herbal Medicine. Beaconsfield, England: Beaconsfield Publishers.

Wichtl, M. and N.G. Bisset (eds.). 1994. Herbal Drugs and Phytopharmaceuticals. Stuttgart: Medpharm Scientific Publishers.

Additional Resources

Braun, R. et al. 1997. Standardzulassungen f r FertigarzneimittelText and Kommentar. Stuttgart: Deutscher Apotheker Verlag.

Deutsches Arzneibuch, 10th ed. Vol. 16. (DAB 10). 1991. Kommentar. Stuttgart: Wissenschaftliche Verlagsgesellschaft.

Polanowski A, et al. 1987. Protein inhibitors of trypsin from the seeds of Cucurbitaceae plants. Acta Biochim Pol 34(4):395406.

Weidhase, R.A. and B. Parthier. 1983. Peptide hydrolase activities in seedlings and hormone-treated cotyledons of pumpkin (Cucurbita pepo). Biomed Biochim Acta 42(78):897906.

This material was adapted from The Complete German Commission E MonographsTherapeutic Guide to Herbal Medicines. M. Blumenthal, W.R. Busse, A. Goldberg, J. Gruenwald, T. Hall, C.W. Riggins, R.S. Rister (eds.) S. Klein and R.S. Rister (trans.). 1998. Austin: American Botanical Council; Boston: Integrative Medicine Communications.

1) The Overview section is new information.

2) Description, Chemistry and Pharmacology, Uses, Contraindications, Side Effects, Interactions with Other Drugs, and Dosage sections have been drawn from the original work. Additional information has been added in some or all of these sections, as noted with references.

3) The dosage for equivalent preparations (tea infusion, fluidextract, and tincture) have been provided based on the following example:

  • Unless otherwise prescribed: 2 g per day of [powdered, crushed, cut or whole] [plant part]
  • Infusion: 2 g in 150 ml of water
  • Fluidextract 1:1 (g/ml): 2 ml
  • Tincture 1:5 (g/ml): 10 ml

4) The References and Additional Resources sections are new sections. Additional Resources are not cited in the monograph but are included for research purposes.

This monograph, published by the Commission E in 1994, was modified based on new scientific research. It contains more extensive pharmacological and therapeutic information taken directly from the Commission E.

Excerpt from Herbal Medicine: Expanded Commission E Monographs
Copyright 2000 American Botanical Council
Published by Integrative Medicine Communications
Available from the American Botanical Council.