Horehound

White horehound/Drug Interactions:

  • 5-HT receptor agonists (triptans)5-HT receptor agonists (triptans): Preclinical studies suggest that white horehound may antagonize the effects of serotonin (1).
  • AnalgesicsAnalgesics: In vivo models of pain in mice report significant analgesic activity of the hydroalcoholic extract of Marrubium vulgare, and antinociceptive effects as well as an anti-inflammatory effects of marrubiin (24). In animal research, naloxone lacked in influence on the antinociceptive action of marrubiin; although the exact mechanism of the antinociceptive action was unclear, inhibition of opioid receptors was lacking (7).
  • AnestheticsAnesthetics: According to secondary sources, white horehound may interfere with the action of inhaled anesthetics.
  • AntiarrhythmicsAntiarrhythmics: In animal study, large amounts of white horehound have caused arrhythmias (1).
  • AntibioticsAntibiotics: The essential oil of M. vulgare showed significant antibacterial activity against Gram (+) bacteria. However, the antibacterial effect of M. vulgare against Gram (-) bacteria was less potent (25). When assessed for antibacterial activity against H. pylori using a broth dilution method, M. vulgare showed a 50% minimum inhibitory concentration within the range of <400mcg/mL (26). The water remaining after hydrodistillation of M. vulgare showed antibacterial activity against Paenibacillus larvae; however, the antibacterial effects of the essential oils of the plant was less than that of the water remaining after hydrodistillation (27).
  • Antidepressant agents, selective serotonin reuptake inhibitors (SSRIs)Antidepressant agents, selective serotonin reuptake inhibitors (SSRIs): Preclinical studies suggest that white horehound may antagonize the effects of serotonin (1).
  • Antidiabetic agentsAntidiabetic agents: Based on clinical and animal study, white horehound may have blood glucose-lowering activity (20; 2; 19).
  • AntiemeticsAntiemetics: White horehound is considered to be an emetic and cathartic in large doses, due to its proposed mechanism of action on the gastrointestinal tract. Theoretically, white horehound may interact with serotonin receptor antagonists such as ondansetron, based on in vitro studies suggesting serotonin-antagonizing effects (1).
  • AntifungalsAntifungals: In vitro, M. vulgare essential oil exhibited strongest antifungal activity against Botrytis cinerea, but showed less potent antifungal activity against Fusarium solani, Penicillium digitatum, and Aspergillus niger (25).
  • AntihypertensivesAntihypertensives: In animal research, white horehound may have hypotensive effects (3; 21).
  • AntilipemicsAntilipemics: In patients with type 2 diabetes treated with Marrubium vulgare, cholesterol and triglyceride levels were lowered by 4.16% and 5.78%, respectively (19).
  • AntineoplasticsAntineoplastics: In vitro, the essential oil of M. vulgare inhibited HeLa cell proliferation, with an IC50 value of 0.258mcg/mL (25). In other in vitro research, ladanein, a constituent of Marrubium vulgare, showed moderate cytotoxic effects against various leukemia cell lines, including K562, K562R, and 697 human leukemia cells, but lacked cytotoxicity against MOLM13 or human peripheral blood mononuclear cells (28).
  • AntispasmodicsAntispasmodics: A hydroalcoholic extract of Marrubium vulgare exhibited antispasmodic effects in animals (7; 6).
  • Antiulcer and gastric acid-reducing agentsAntiulcer and gastric acid-reducing agents: Marrubiin and methanol extract from Marrubium vulgare leaves were shown to have a curative effect on ethanol-induced ulcers and to inhibit the formation of indomethacin-induced ulcers in animal research (29). In addition, treatment with marrubiin and M. vulgare leaf extract increased pH and mucus production in animal research (29).
  • Bile acid sequestrantsBile acid sequestrants: In a 1959 study, the white horehound constituent marrubic acid and its sodium salt were reported to transiently stimulate bile flow in rats, while the constituent marrubiin lacked this effect (8).
  • Cytochrome P450 2D6 substratesCytochrome P450 2D6 substrates: According to secondary sources, white horehound acts as a cytochrome P450 2D6 inhibitor.
  • DiureticsDiuretics: According to secondary sources, white horehound may have aldosterone-enhancing properties, and thus may alter the effects of diuretics, particularly aldosterone-antagonist diuretics.
  • EstrogensEstrogens: According to secondary sources, white horehound may contain phytoestrogenic compounds. Theoretically, white horehound may interfere with estrogen therapy.
  • ExpectorantsExpectorants: Monoterpenes from the volatile oil of Marrubium vulgare have exhibited expectorant activity (30). The effect of concomitant use with other expectorants is unclear.
  • Fertility agentsFertility agents: In animal research, Marrubium vulgare has been shown to have emmenagogic and abortifacient effects (4; 5). In addition, anecdotal reports have noted that white horehound may stimulate uterine contractions.
  • Gastrointestinal agentsGastrointestinal agents: White horehound is considered to be an emetic and cathartic in large doses and may cause diarrhea due to its proposed mechanism of action on the gastrointestinal tract. White horehound may cause intestinal dilation or ileus due to proposed aldosterone-enhancing properties.
  • HepatotoxinsHepatotoxins: A terpenoid constituent of Marrubium vulgare, marrubic acid, was shown to induce a 40.16% reduction in serum glutamate oxaloacetate transaminase (SGOT), a 35.06% reduction in serum glutamate pyruvate oxaloacetate transaminase (SGPT), and a 30.51% reduction in alkaline phosphatase (ALP); in addition, this constituent was shown to increase levels of total protein by 34.07% (13).
  • Hormonal agentsHormonal agents: Due to proposed hypothalamic-pituitary-gonadal axis (HPA) effects of white horehound constituents, various hormonal levels may theoretically be altered, although there is limited human clinical information in this area. White horehound may contain phytoestrogenic compounds that may interfere with estrogen therapy.
  • ImmunostimulantsImmunostimulants: In vitro, Marrubium vulgare increased proliferation of splenocytes; this effect was attributed to the immunostimulatory activity of the plant (14).
  • ImmunosuppressantsImmunosuppressants: In vitro, Marrubium vulgare increased proliferation of splenocytes; this effect was attributed to the immunostimulatory activity of the plant (14).
  • PenicillinsPenicillins: Anecdotal reports suggest that white horehound may interact with the excretion of penicillin, although details and scientific data are limited.
  • PesticidesPesticides: When assessed for molluscicidal activity against the adults and eggs of Biomphalaria alexandrina, the essential oils of Marrubium vulgare L. were reported to show an LC50 and LC90 of 50 and 100ppm/three hours against adults and an LC100 of 200ppm/24 hours against eggs (15). When assessed for mosquitocidal activity against Culex pipiens, M. vulgare showed an LC50 of 200ppm/12 hours against both larvae and pupae (15).
  • VasodilatorsVasodilators: In animal research, white horehound may have vascular relaxant activity (3; 12).
  • VasopressorsVasopressors: In animal research, white horehound may have vascular relaxant activity (3; 12).

    • White horehound/Herb/Supplement Interactions:

  • AnalgesicsAnalgesics: In vivo models of pain in mice report significant analgesic activity of the hydroalcoholic extract of Marrubium vulgare, and antinociceptive effects as well as an anti-inflammatory effects of marrubiin (24). In animal research, naloxone lacked in influence on the antinociceptive action of marrubiin; although the exact mechanism of the antinociceptive action was unclear, inhibition of opioid receptors was lacking (7).
  • AnestheticsAnesthetics: According to secondary sources, white horehound may interfere with the action of inhaled anesthetics.
  • AntiarrhythmicsAntiarrhythmics: In animal study, large amounts of white horehound have caused arrhythmias (1).
  • AntibacterialsAntibacterials: The essential oil of M. vulgare showed significant antibacterial activity against Gram (+) bacteria. However, the antibacterial effect of M. vulgare against Gram (-) bacteria was less potent (25). When assessed for antibacterial activity against H. pylori using a broth dilution method, M. vulgare showed a 50% minimum inhibitory concentration within the range of <400mcg/mL (26). The water remaining after hydrodistillation of M. vulgare showed antibacterial activity against Paenibacillus larvae; however, the antibacterial effects of the essential oils of the plant was less than that of the water remaining after hydrodistillation (27).
  • Antidepressant agents, selective serotonin reuptake inhibitors (SSRIs)Antidepressant agents, selective serotonin reuptake inhibitors (SSRIs): Preclinical studies suggest that white horehound may antagonize the effects of serotonin (1).
  • AntiemeticsAntiemetics: White horehound is considered to be an emetic and cathartic in large doses, due to its proposed mechanism of action on the gastrointestinal tract. Theoretically, white horehound may interact with serotonin receptor antagonists such as ondansetron, based on in vitro studies that suggest potential serotonin-antagonizing effects (1).
  • AntifungalsAntifungals: In vitro, M. vulgare essential oil exhibited strongest antifungal activity against Botrytis cinerea, but showed less potent antifungal activity against Fusarium solani, Penicillium digitatum, and Aspergillus niger (25).
  • AntilipemicsAntilipemics: In patients with type 2 diabetes treated with Marrubium vulgare, cholesterol and triglyceride levels were lowered by 4.16% and 5.78%, respectively (19).
  • AntineoplasticsAntineoplastics: In vitro, the essential oil of M. vulgare inhibited HeLa cell proliferation, with an IC50 value of 0.258mcg/mL (25). In other in vitro research, ladanein, a constituent of Marrubium vulgare, showed moderate cytotoxic effects against various leukemia cell lines, including K562, K562R, and 697 human leukemia cells, but lacked cytotoxicity against MOLM13 or human peripheral blood mononuclear cells (28).
  • AntioxidantAntioxidant: Using pyranine as a probe to assess the antioxidant capacities of various plant extracts towards hypochlorite, Marribium vulgare was shown to protect pyranine; the authors attributed this effect to the antioxidant effects of this plant (31). However, in other laboratory research, the antioxidant activity of Marrubium vulgare was reported to be less than that of various species of Lamiaceae and Salvia (32).
  • AntispasmodicsAntispasmodics: A hydroalcoholic extract of Marrubium vulgare has been shown to exhibit antispasmodic effects in animals (7).
  • Antiulcer and gastric acid-reducing agentsAntiulcer and gastric acid-reducing agents: Marrubiin and methanol extract from Marrubium vulgare leaves were shown to have a curative effect on ethanol-induced ulcers and to inhibit the formation of indomethacin-induced ulcers in animal research (29). In addition, treatment with marrubiin and M. vulgare leaf extract was shown to increase pH and mucus production in animal research (29).
  • Bile acid sequestrantsBile acid sequestrants: In a 1959 study, the white horehound constituent marrubic acid and its sodium salt were reported to transiently stimulate bile flow in rats, while the constituent marrubiin lacked this effect (8).
  • Cytochrome P450 2D6 substratesCytochrome P450 2D6 substrates: According to secondary sources, white horehound acts as a cytochrome P450 2D6 inhibitor.
  • DiureticsDiuretics: According to secondary sources, white horehound may have aldosterone-enhancing properties, and thus may alter the effects of diuretics, particularly aldosterone-antagonist diuretics.
  • ExpectorantsExpectorants: White horehound has proposed expectorant activity. The effects of concomitant use with other expectorants is unclear.
  • Fertility agentsFertility agents: In animal research, Marrubium vulgare has been shown to have emmenagogic and abortifacient effects (4; 5). In addition, anecdotal reports have noted that white horehound may stimulate uterine contractions.
  • Gastrointestinal agentsGastrointestinal agents: White horehound is considered to be an emetic and cathartic in large doses and may cause diarrhea due to its proposed mechanism of action on the gastrointestinal tract. White horehound may cause intestinal dilation or ileus due to proposed aldosterone-enhancing properties.
  • Hepatoprotective agentsHepatoprotective agents: A terpenoid constituent of Marrubium vulgare, marrubic acid, was shown to induce a 40.16% reduction in serum glutamate oxaloacetate transaminase (SGOT), a 35.06% reduction in serum glutamate pyruvate oxaloacetate transaminase (SGPT), and a 30.51% reduction in alkaline phosphatase (ALP); in addition, this constituent was shown to increase levels of total protein by 34.07% (13).
  • HepatotoxinsHepatotoxins: A terpenoid constituent of Marrubium vulgare, marrubic acid, was shown to induce a 40.16% reduction in serum glutamate oxaloacetate transaminase (SGOT), a 35.06% reduction in serum glutamate pyruvate oxaloacetate transaminase (SGPT), and a 30.51% reduction in alkaline phosphatase (ALP); in addition, this constituent was shown to increase levels of total protein by 34.07% (13).
  • Hormonal agentsHormonal agents: Due to proposed hypothalamic-pituitary-gonadal axis (HPA) effects of white horehound constituents, various hormonal levels may theoretically be altered, although there is limited human clinical information in this area. White horehound may contain phytoestrogenic compounds that may interfere with estrogen therapy.
  • HypoglycemicsHypoglycemics: Based on clinical and animal study, white horehound may have blood glucose-lowering activity (20; 2; 19).
  • HypotensivesHypotensives: In animal research, white horehound may have hypotensive effects (3; 21).
  • ImmunomodulatorsImmunomodulators: In vitro, Marrubium vulgare was shown increase proliferation of splenocytes; this effects was attributed to the immunostimulatory activity of the plant (14).
  • PesticidesPesticides: When assessed for molluscicidal activity against the adults and eggs of Biomphalaria alexandrina, the essential oils of Marrubium vulgare L. were reported to show an LC50 and LC90 of 50 and 100ppm/three hours against adults and an LC100 of 200ppm/24 hours against eggs (15). When assessed for mosquitocidal activity against Culex pipiens, M. vulgare showed an LC50 of 200ppm/12 hours against both larvae and pupae (15).
  • PhytoestrogensPhytoestrogens: According to secondary sources, white horehound may contain phytoestrogenic compounds. Theoretically, white horehound may interfere with estrogen therapy.
  • VasodilatorsVasodilators: According to animal research, white horehound may have vascular relaxant activity (3; 12).
  • VasopressorsVasopressors: According to animal research, white horehound may have vascular relaxant activity (3; 12).

    • White horehound/Food Interactions:

  • Insufficient available evidence.

    • White horehound/Lab Interactions:

  • Blood glucoseBlood glucose: According to clinical and animal study, white horehound may have blood glucose-lowering activity (20; 2; 19).
  • Blood pressureBlood pressure: According to animal research, white horehound may have hypotensive effects (3; 21).
  • EKGEKG: In animal research, large amounts of white horehound have caused arrhythmias (1).
  • Lipid profileLipid profile: In patients with type 2 diabetes treated with Marrubium vulgare, cholesterol and triglyceride levels were lowered by 4.16% and 5.78%, respectively (19).
  • Serum electrolytesSerum electrolytes: Potassium and sodium levels may theoretically be altered, due to the proposed aldosterone-enhancing activity of white horehound.
  • Serum hormone levelsSerum hormone levels: Due to proposed hypothalamic-pituitary-gonadal axis (HPA) effects of white horehound constituents, various hormonal levels may theoretically be altered, although there is limited human clinical information in this area. White horehound may contain phytoestrogenic compounds.