2-methy-3-butene-2-ol, 8-PN, 8-prenylnaringenin, beer, Cannabaceae (family), colupulone, common hops, European hops, hop, hop strobile, Hopfen (German), houblon (French), humulon, humulus, Humulus lupulus, iso-alpha-acids, lupulin, lupulus, Lupuli strobulus, prenylated 2©-hydroxychalcones, prenylflavonoids, spent hops, xanthohumol, Ze 91019.
The hop is a member of the Cannabaceae family, traditionally used for relaxation, sedation, and to treat insomnia. A number of methodologically weak human trials have investigated hops in combination with valerian (Valeriana officinalis) for the treatment of sleep disturbances, and several animal studies have examined the sedative properties of hops alone. However, the results of these studies are equivocal, and there is currently insufficient evidence to recommend hops alone or in combination for any medical condition.
Hops are also sometimes found in combination products with passionflower (Passiflora incarnata), skullcap (potentially damaging to the liver), or with a high percentage of alcohol (up to 70% grain alcohol), confounding the association between the herb and possible sedative or hypnotic effects.
Hops contain phytoestrogens that may possess estrogen receptor agonist or antagonist properties with unclear effects on hormone-sensitive conditions, such as breast, uterine, cervical, or prostate cancer or endometriosis.
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.
Animal studies report that hops may have sedative and sleep-enhancing (hypnotic) effects. However, little human research has evaluated the effects of hops on sleep quality. Further study is needed in this area before a strong recommendation can be made.
When used in combination with other products, hops may help alleviate menopausal symptoms, such as hot flashes and difficulty sleeping, because it has estrogen-like activity. However, until more well-designed studies are performed, a strong recommendation cannot be made.
Early clinical research suggests that a combination formula containing hops may help reduce symptoms of rheumatic diseases, such as osteoarthritis, rheumatoid arthritis, and fibromyalgia. However, well-designed human trials using hops alone are needed to determine if these positive effects are specifically the result of hops.
Hops have been used traditionally as a sedative, for relaxation and reduction of anxiety. Although some animal studies suggest possible sedative properties, there is limited human research in this area. Better studies are needed before a firm conclusion can be drawn.
*Key to grades:
A: Strong scientific evidence for this use;
B: Good scientific evidence for this use;
C: Unclear scientific evidence for this use;
D: Fair scientific evidence against this use (it may not work);
F: Strong scientific evidence against this use (it likely does not work).
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. Analgesic, antidepressant, antibacterial (antimycobacterial), antifungal, anti-inflammatory, antispasmodic, antiviral (anti-HCV, anti-Rhino, anti-herpes virus), anxiety, aphrodisiac, appetite stimulant, asbestosis, atherosclerosis (hardening of the arteries), atopic dermatitis, breast enhancer, cancer (breast, uterine, cervical, prostate), Crohn's disease, depression, diabetes, digestion, dysentery, dyspepsia, Epstein-Barr virus, estrogen-like activity, heartburn, high cholesterol, irritable bowel syndrome (IBS), kidney disorders, leprosy, leukemia (HL-60 ), mood disturbances, muscle spasm, nervous disorders, obesity, osteoporosis, pain, parasites and worms, restlessness, skin ulcers (topical), spine problems (scoliosis), tuberculosis.
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)
For insomnia or sleep disturbances, studies have used 300 to 400 milligrams of hops extract combined with 240 to 300 milligrams of valerian extract, taken by mouth before bed. Traditionally, doses of 0.5 to 1.0 gram of dried hops extract or 0.5 to 1.0 milliliter of liquid hops extract (1:1 in 45% alcohol) have been taken up to three times daily, although using hops alone has not been well studied.
Intravenous/intramuscular dosing is not recommended.
Children (younger than 18 years)
Hops extract is traditionally considered to be one of the milder sedative herbs and to be safe for children. However, there is limited research in this area and safety has not been clearly established.
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.
Rash (contact dermatitis) and difficulty breathing have been reported mainly in hops harvesters. Allergy to hops pollen has also been reported. Hops allergy has been reported in a patient with previous severe allergic reactions to peanut, chestnut, and banana. Therefore people allergic to any of these agents should avoid hops.
Side Effects and Warnings
Dry cough, difficulty breathing, chronic bronchitis, and other occupational respiratory diseases have been associated with hops. Dust from hops can contain harmful bacteria. Long-term breathing problems have been reported.
Hops may cause mild central nervous system (CNS) depression (drowsiness, slowed breathing and thinking), especially when taken with drugs or herbs/supplements that also cause CNS depression. Caution is advised while driving or operating machinery.
Eating hops in large quantities may cause seizure, hyperthermia, restlessness, vomiting, stomach pain, and increased stomach acid. It is unclear what effects may occur in hormone-sensitive conditions such as cancer (breast, uterine, cervical, prostate) or endometriosis.
Hops may lower blood sugar levels in normal individuals, but may actually increase blood sugar in those with diabetes. Caution is advised in patients with diabetes or hypoglycemia and in those taking drugs, herbs, or supplements that affect blood sugar. Serum glucose levels may need to be monitored by a healthcare provider, and medication adjustments may be necessary.
Pregnancy and Breastfeeding
Hops are not recommended during pregnancy or lactation due to possible hormonal and sedative effects. Limited research is available in these areas. Many tinctures contain high levels of alcohol and should be avoided during pregnancy.
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
Hops may cause mild central nervous system (CNS) depression (drowsiness, slowed breathing, and thinking) and may add to the effects of drugs that also cause CNS depression or sedation. Examples include benzodiazepines such as lorazepam (Ativan©) or diazepam (Valium©), barbiturates such as phenobarbital, narcotics such as codeine, some antidepressants, and alcohol. Caution is advised while driving or operating machinery.
Based on preliminary animal studies, hops may lower blood sugar levels in normal individuals, but may actually increase blood sugar in those with diabetes. Caution is advised when using medications that may lower blood sugar. Patients taking drugs for diabetes by mouth or patients taking insulin should be monitored closely by a qualified healthcare provider. Medication adjustments may be necessary.
Laboratory research shows that estrogen-like substances in hops may have stimulatory or inhibitory effects on estrogen-sensitive parts of the body. It is not clear what interactions may occur when used with other hormonal therapies such as birth control pills, hormone replacement therapy, tamoxifen, or aromatase inhibitors like letrozole (Femara©).
Hops may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of these drugs may be decreased in the blood and the intended effects may be reduced. Patients using any medications should check the package insert and speak with a healthcare professional or pharmacist about possible interactions.
Taking phenothiazine anti-psychotic drugs with hops is said to possibly increase the risk of hyperthermia (increased body temperature), although there is a lack of reliable human studies in this area.
Many tinctures contain high levels of alcohol and may cause nausea or vomiting when taken with metronidazole (Flagyl©) or disulfiram (Antabuse©).
Hops compounds have also been shown to reduce triglycerides and free fatty acid blood levels and therefore may have additive effects with cholesterol-lowering drugs such as lovastatin (Mevacor©).
Hops may also interact with antibiotic, antidepressant, antifungal, anti-inflammatory, and gastrointestinal drugs.
Interactions with Herbs and Dietary Supplements
Hops may cause mild central nervous system (CNS) depression (drowsiness, slowed breathing, and thinking) and may add to the effects of herbs or supplements that also cause CNS depression or sedation. Caution is advised while driving or operating machinery.
Based on preliminary animal studies, hops may lower blood sugar levels in normal individuals, but may actually increase blood sugar in those with diabetes. Caution is advised when using herbs or supplements that may affect blood sugar. Blood glucose levels may require monitoring, and doses may need adjustment.
Hops may interfere with the way the body processes certain drugs using the liver's "cytochrome P450" enzyme system. As a result, the levels of other herbs or supplements may become too low in the blood. It may also alter the effects that other herbs or supplements potentially may have on the P450 system. Patients using any medications should check the package insert and speak with a healthcare professional, including a pharmacist, about possible interactions.
Because hops contain estrogen-like chemicals, the effects of other agents believed to have estrogen-like properties may be altered.
Hops compounds have also been shown to reduce triglycerides and free fatty acid blood levels and therefore may have additive effects with cholesterol-lowering herbs and supplements such as guggul or red yeast.
Hops may also interact with antibacterial, antidepressant, antifungal, anti-inflammatory, antineoplastic, antioxidant, antipsychotic, and gastrointestinal supplements.
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).
Natural Standard Bottom Line Monograph, Copyright © 2011 (www.naturalstandard.com). Commercial distribution prohibited. This monograph is intended for informational purposes only, and should not be interpreted as specific medical advice. You should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.
While some complementary and alternative techniques have been studied scientifically, high-quality data regarding safety, effectiveness, and mechanism of action are limited or controversial for most therapies. Whenever possible, it is recommended that practitioners be licensed by a recognized professional organization that adheres to clearly published standards. In addition, before starting a new technique or engaging a practitioner, it is recommended that patients speak with their primary healthcare provider(s). Potential benefits, risks (including financial costs), and alternatives should be carefully considered. The below monograph is designed to provide historical background and an overview of clinically-oriented research, and neither advocates for or against the use of a particular therapy.
The information in this monograph is intended for informational purposes only, and is meant to help users better understand health concerns. Information is based on review of scientific research data, historical practice patterns, and clinical experience. This information should not be interpreted as specific medical advice. Users should consult with a qualified healthcare provider for specific questions regarding therapies, diagnosis and/or health conditions, prior to making therapeutic decisions.
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Copyright © 2011 Natural Standard (www.naturalstandard.com)
Copyright © 2011 Natural Standard (www.naturalstandard.com)