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.
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.
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.
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.
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.
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.
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.
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.
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.
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 professional level monograph edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com): Ethan Basch, MD (Natural Standard Research Collaboration); Samuel Basch, MD (Mt. Sinai Medical Center); Dawn Costa, BA, BS (Natural Standard Research Collaboration); Cynthia Dacey, PharmD (Natural Standard Research Collaboration); Paul Hammerness, MD (Harvard Medical School); Jenna Hollenstein, MS, RD (Natural Standard Research Collaboration); Carolyn Williams Orlando, MA (Harvard Medical School); Shaina Tanguay-Colucci, BS (Natural Standard Research Collaboration); Catherine Ulbricht, PharmD (Massachusetts General Hospital); Mamta Vora, PharmD (Northeastern University); Wendy Weissner, BA (Natural Standard Research Collaboration).
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Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.