Barley

Barley/Drug Interactions:

  • AnthelminticsAnthelmintics: In animal research, a diet supplemented with barley reduced the bioavailability of triclabendazole (78); theoretically, barley may have a similar effect on anthelmintics.
  • AntidiabeticsAntidiabetics: Barley contains more fermentable carbohydrate than other cereals, such as rice. In a clinical trial, fermentation of undigested carbohydrate produced short-chain fatty acids, some which may reduce hepatic glucose production and affect postprandial glycemia (67). In clinical trials, barley resulted in lowered blood glucose concentrations (40; 41); theoretically, concomitant use may result in lower-than-expected blood glucose values.
  • AntihypertensivesAntihypertensives: In a clinical trial, a combination of whole wheat, brown rice, and barley decreased blood pressure (42). However, this effect may be due to the whole wheat and brown rice, as barley alone did not decrease blood pressure.
  • AntilipemicsAntilipemics: In clinical, animal, and in vitro research, barley use has been associated with decreased total and low-density lipoprotein (LDL) cholesterol concentrations, and may act additively with other cholesterol-lowering agents (43; 3; 4; 44; 45; 46). Constituents such as tocotrienols (3), beta-glucan (4; 79; 80), and d-alpha-tocotrienol (81) may play an active role in barley's antilipemic effects.
  • Gastrointestinal agentsGastrointestinal agents: Germinated barley foodstuff (GBF) appeared to induce proliferation of intestinal epithelial cells and facilitate defecation through bacterial production of short-chain fatty acids, especially butyrate. In human research, GBF has been associated with increased growth of microflora in the intestinal tract (82; 54).
  • Orally administered agentsOrally administered agents: Theoretically, fiber may reduce gastrointestinal transit and may modulate the absorption of various orally administered agents.
  • SympathomimeticsSympathomimetics: Hordenine, an aminophenol in the root of germinating barley, is a sympathomimetic (47). Theoretically, concomitant use may result in additive effects. Human data, however, are lacking in this area.

    • Barley/Herb/Supplement Interactions:

  • AnthelminticsAnthelmintics: In animal research, a diet supplemented with barley reduced the bioavailability of triclabendazole (78); theoretically, barley may have a similar effect on anthelmintics.
  • AntilipemicsAntilipemics: In clinical, animal, and in vitro research, barley use has been associated with decreased total and low-density lipoprotein (LDL) cholesterol concentrations, and may act additively with other cholesterol-lowering agents, such as niacin, garlic, guggul, or fish oil (43; 3; 4; 44; 45; 46). Constituents such as tocotrienols (3), beta-glucan (4; 79; 80), and d-alpha-tocotrienol (81) may play an active role in barley's antilipemic effects.
  • Gastrointestinal agentsGastrointestinal agents: Germinated barley foodstuff (GBF) appears to induce proliferation of intestinal epithelial cells and facilitate defecation through bacterial production of short-chain fatty acids, especially butyrate. In human research, GBF has been associated with increased growth of microflora in the intestinal tract (82; 54).
  • HypoglycemicsHypoglycemics: Barley contains more fermentable carbohydrate than other cereals, such as rice. In a clinical trial, fermentation of undigested carbohydrate produced short-chain fatty acids, some which may reduce hepatic glucose production and affect postprandial glycemia (67). In clinical trials, barley resulted in lowered blood glucose concentrations (40; 41); theoretically, concomitant use may result in lower-than-expected blood glucose values.
  • HypotensivesHypotensives: In a clinical trial, a combination of whole wheat, brown rice, and barley decreased blood pressure (42). However, this effect may be due to the whole wheat and brown rice, as barley alone did not decrease blood pressure.
  • Orally administered agentsOrally administered agents: Theoretically, fiber may reduce gastrointestinal transit and may modulate the absorption of various orally administered agents.
  • SympathomimeticsSympathomimetics: Hordenine, an aminophenol in the root of germinating barley, is a sympathomimetic (47). Theoretically, combination use may result in additive effects. Human data, however, are lacking in this area.

    • Barley/Food Interactions:

  • Brown riceBrown rice: According to a clinical trial, a combination of whole wheat, brown rice, and barley may decrease blood pressure. However, this effect may be due to the whole wheat and brown rice, as barley alone did not decrease blood pressure (42).
  • High-carbohydrate foodsHigh-carbohydrate foods: According to clinical research, a high dose of barley beta-glucan supplement may improve glucose control taken with high-carbohydrate foods, but not when added to a high-carbohydrate beverage (40).
  • Whole wheatWhole wheat: According to a clinical trial, a combination of whole wheat, brown rice, and barley may decrease blood pressure. However, this effect may be due to the whole wheat and brown rice, as barley alone did not decrease blood pressure (42).

    • Barley/Lab Interactions:

  • Blood glucoseBlood glucose: Barley contains more fermentable carbohydrate than other cereals, such as rice. In a clinical trial, fermentation of undigested carbohydrate produced short-chain fatty acids, some of which may reduce hepatic glucose production and affect postprandial glycemia (67).
  • Blood pressureBlood pressure: In a clinical trial, a combination of whole wheat, brown rice, and barley decreased blood pressure (42). However, this effect may be due to the whole wheat and brown rice, as barley alone did not decrease blood pressure.
  • C-reactive proteinC-reactive protein: In a clinical trial, low-molecular-weight barley was found to decrease C-reactive protein levels (7).
  • Hydrogen (H2) breath test: Hydrogen (H2) breath test: In a clinical trial, not all of the carbohydrate in barley was absorbed; this led to fermentation in the colon by microflora, measurable by the H2 breath test (67).
  • Insulin levelsInsulin levels: In clinical trials, barley decreased insulinemic indices (40; 41).
  • Lipid panelLipid panel: In clinical, animal, and in vitro research, barley use has been associated with decreased total and low-density lipoprotein (LDL) cholesterol concentrations (43; 3; 4; 44; 7).
  • Urine drug screensUrine drug screens: According to comparative research, hordenine, a constituent of barley, may yield false positive results with enzyme-linked immunosorbent assay (ELISA) and thin-layer chromatograph (TLC) assays for various opiate drugs (47).