Hops : Safety

by MedlinePlus

(Page 2 of 2)

Pregnancy and Breastfeeding

Hops is 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.

Interactions

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 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 reduce the intended effects. If you are using any medications, check the package insert and speak with your healthcare provider or pharmacist about possible interactions.

Taking phenothiazine anti-psychotic drugs with hops is said to possibly increase the risk of hyperthermia, although there are no 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®).

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. Examples include: calamus, calendula, California poppy, capsicum, catnip, celery, couch grass, dogwood, elecampane, German chamomile, goldenseal, gotu kola, kava (may help sleep without drowsiness), lavender aromatherapy, lemon balm, sage, sassafras, skullcap, shepherd's purse, Siberian ginseng, St. John's wort, stinging nettle, valerian, wild carrot, wild lettuce, withania root, and yerba mansa. 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. Examples of agents that may lower blood sugar include: Aloe vera , American ginseng, bilberry, bitter melon, burdock, fenugreek, fish oil, gymnema, horse chestnut seed extract (HCSE), marshmallow, milk thistle, Panax ginseng, rosemary, Siberian ginseng, stinging nettle and white horehound. Agents that may raise blood sugar levels include arginine, cocoa, and ephedra (when combined with caffeine).

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 to be too low in the blood. It may also alter the effects that other herbs or supplements potentially may have on the P450 system, such as bloodroot, cat's claw, chamomile, chaparral, chasteberry, damiana, Echinacea angustifolia , goldenseal, grapefruit juice, licorice, oregano, red clover, St. John's wort, wild cherry, and yucca. If you are using any medications, check the package insert and speak with your healthcare provider or pharmacist about possible interactions.

Because hops contain estrogen like chemicals, the effects of other agents believed to have estrogen-like properties may be altered. Possible examples include alfalfa, black cohosh, bloodroot, burdock, hops, kudzu, licorice, pomegranate, red clover, soy, thyme, white horehound, and yucca.

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.

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