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Humulus Lupulus
Natural Encyclopaedia

Hops

FAMILY: Cannabaceae. It has been known since ancient times for its soporific and calming effects. Workers in the old breweries, when processing hops, felt drowsy after a long time and had to stop work periodically to avoid falling asleep.

HABITAT: all of Europe and North America. Currently also cultivated in Australia and South America.

PUSED ART: inflorescences with a characteristic aromatic odour.

PHARMACEUTICAL PREPARATIONS: nebulised dry extract titrated in total flavonoids min. 4% and in essential oil min. 0.3% (French Pharmacopoeia X), whose daily dose ranges from 10 to 13 mg/kg, divided into two administrations, preferably between meals.

CHEMICAL COMPOSITION:  is a plant drug rich in flavonoids, such as astragaloside, xanthohumol min.0.2% and isoxanthohumol. It contains about 1% essential oil (min. 0.3%), consisting mainly of mono- and sesquiterpene carbons. The compounds responsible for the characteristic hop flavour are lupulone, umulone and derived compounds, the content of which ranges from 15 to 30%.

THERAPEUTIC PROPERTIES:
Action on the central nervous system. It has a sedative effect on the central nervous system, and is a good nervous balancer for various states of anxiety.
A controlled clinical trial investigated the effect on sleep of a valerian-luppol combination versus diphenhydramine and versus placebo. 184 patients at 9 sleep centres in the United States with moderate insomnia were enrolled. They received by mouth shortly before bedtime either 2 capsules of a product containing 187 mg dry extract of valerian and 42 mg dry extract of hops or 2 capsules of diphenhydramine (a chemical sleeping pill) of 25 mg each for 14 days followed by placebo for another 14 days or a placebo for 28 days. Sleep parameters were assessed by means of appropriate tests. With none of the treatments used were alterations noted in sleep stages 3 and 4 and in the REM phase of sleep itself. Quality of life was significantly better in the valerian-luppol group than in the diphenhydramine and placebo groups. No significant side effects were observed in any of the groups tested. The study indicates that the valerian-lupple combination is effective in promoting sleep and especially in improving quality of life in patients with moderate insomnia.

Action on the endocrine system. Hops contain substances with an action similar to that of oestrogen. The most important of these is 8-prenylnaringenin, which is a flavonoid.
A controlled clinical study examined the effect on neurovegetative disorders of the menopause of a hydroalcoholic extract of hops enriched with 8-prenylnaringenin, a phytoestrogen. Sixty-seven postmenopausal women were enrolled, taking either the extract or a placebo for three months. It was noted that there was a significant improvement in neurovegetative complaints of the menopause in both groups, but hop extract provided significantly better results than placebo after 6 weeks. The study indicates that hop extract containing 8-prenylnaringenin is more effective than placebo in alleviating the neurovegetative complaints of the menopause, particularly after 6 weeks of therapy.

SIDE EFFECTS: at high doses, stomach upset with nausea, dizziness, diarrhoeal phenomena and menstrual disorders in women may occur, albeit rarely.

CONTRAINDICATIONS: It should not be used if there are contraindications to the use of substances with oestrogenic action. It should not be used during pregnancy and lactation.

DRUG INTERACTIONS: not known.

Si può trovare tra le componenti di vagonotte® e vagonotte mel® 

Bibliography

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Hajirahimkhan A. et al. Evaluation of estrogenic activity of licorice species in comparison with Hops used in botanicals for menopausal symptoms. PLoS One. 8(7):e67947. doi: 10.1371/journal.pone.0067947. Print 2013.
Yuan Y. et al. Inhibition of human cytochrome P450 enzymes by hops (Humulus lupulus) and hop prenylphenols. Eur J Pharm Sci. 2013 Dec 14;53C:55-61. doi: 10.1016/j.ejps.2013.12.003. [Epub ahead of print]
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