Mahonia aquifolium

Oregon grape/Drug Interactions:

  • AntibioticsAntibiotics: In vitro, crude extracts of Mahonia aquifolium (Pursh) Nutt. stem bark, as well as its constituents berberine and jatrorrhizine, have shown antimicrobial activity against gram-positive and gram-negative bacteria (9; 10; 11; 12). The effects of concurrent use of Oregon grape and antibiotics are unclear.
  • AnticonvulsantsAnticonvulsants: According to secondary sources, Oregon grape may have anticonvulsant effects. The effects of concurrent use of anticonvulsant agents and Oregon grape are unclear.
  • AntineoplasticsAntineoplastics: In vitro, berbamine has shown antiproliferative activity against primary leukemia cells (4). In animal study, berbamine enhanced neutrophil and lymphocyte counts, but decreased the number of bone marrow stem cells (5).
  • Cardiovascular agentsCardiovascular agents: In vitro, extracts of Mahonia aquifolium root and its alkaloids berbamine, oxyacanthine, isothebaine, and isocorydine inhibited contractions of rat aorta and induced dilation, potentially due to inhibition of calcium entry into cells (16; 17). The effects of Oregon grape and cardiovascular agents are unclear.
  • CNS depressantsCNS depressants: According to secondary sources, Oregon grape may have sedative effects. The extent of interaction with antianxiety agents is unknown but may theoretically occur.
  • CyclosporineCyclosporine: According to a clinical trial, berberine, a constituent of Oregon grape, increased serum cyclosporine levels, possibly through cytochrome P450 3A4 inhibition (25).
  • Cytochrome P450 substratesCytochrome P450 substrates: According to in vitro study, berberine may moderately inhibit CYP3A4 (26; 27).
  • Gastrointestinal agentsGastrointestinal agents: In clinical study, isolated berberine, a constituent of Oregon grape, has been shown to have antidiarrheal effects in patients with Escherichia coli (28). In animal study, berberine has been shown to inhibit transit time in the intestine (29). According to secondary sources, bitter-tasting compounds as well as alkaloids in Oregon grape may stimulate digestive function such as flow of bile. The effects of Oregon grape with gastrointestinal agents are unclear.
  • ImmunostimulantsImmunostimulants: In vitro, crude extracts and alkaloid fractions obtained from Mahonia aquifolium have shown immunomodulatory activity (18; 19).
  • ImmunosuppressantsImmunosuppressants: In vitro, crude extracts and alkaloid fractions obtained from Mahonia aquifolium have shown immunomodulatory activity (18; 19). The effects of Oregon grape with immunosuppressants are unclear.
  • SedativesSedatives: According to secondary sources, Oregon grape may have sedative effects.
  • TetracyclinesTetracyclines: According to clinical study, berberine may decrease absorption of tetracycline (30; 28). It is unclear if there is significant interaction with doxycycline.
  • Oregon grape/Herb/Supplement Interactions:

  • AntibacterialsAntibacterials: In vitro, the crude extract of Mahonia aquifolium (Pursh) Nutt. stem bark, as well as its constituents berberine and jatrorrhizine, have shown antimicrobial activity against gram-positive and gram-negative bacteria (9; 10; 11; 12).The effects of concurrent use of Oregon grape and antibacterial agents are not well understood.
  • AnticonvulsantsAnticonvulsants: According to secondary sources, Oregon grape may have anticonvulsant effects. The effects of concurrent use of anticonvulsant agents and Oregon grape are unclear.
  • AntineoplasticsAntineoplastics: In vitro, berbamine has shown antiproliferative activity against primary leukemia cells (4). In animal study, berbamine enhanced neutrophil and lymphocyte counts, but decreased the number of bone marrow stem cells (5).
  • AntioxidantsAntioxidants: Several laboratory studies have reported that alkaloids isolated from Mahonia aquifolium showed lipoxygenase inhibitory and antioxidant properties (13; 14; 15).
  • Cardiovascular agentsCardiovascular agents: In vitro, extracts of Mahonia aquifolium root and its alkaloids berbamine, oxyacanthine, isothebaine, and isocorydine inhibited contractions of rat aorta and induced dilation, potentially due to inhibition of calcium entry into cells (16; 17). The effects of Oregon grape and cardiovascular agents are unclear.
  • Cytochrome P450 substratesCytochrome P450 substrates: According to in vitro study, berberine, a constituent of Oregon grape, moderately inhibits CYP3A4 (26; 27).
  • Gastrointestinal agentsGastrointestinal agents: In clinical study, isolated berberine, a constituent of Oregon grape, has been shown to have antidiarrheal effects in patients with Escherichia coli (28). In animal study, berberine has been shown to inhibit transit time in the intestine (29). According to secondary sources, bitter-tasting compounds as well as alkaloids in Oregon grape may stimulate digestive function such as flow of bile. The effects of Oregon grape with gastrointestinal agents unclear.
  • Licorice (Glycyrrhiza spp.)Licorice (Glycyrrhiza spp.): According to secondary sources, Glycyrrhiza counteracts the effects of berberine.
  • ImmunostimulantsImmunostimulants: In vitro, crude extracts and alkaloid fractions obtained from Mahonia aquifolium have shown immunomodulatory activity (18; 19).
  • ImmunosuppressantsImmunosuppressants: In vitro, crude extracts and alkaloid fractions obtained from Mahonia aquifolium have shown immunomodulatory activity (18; 19). The effects of Oregon grape with immunosuppressants are unclear.
  • SedativesSedatives: According to secondary sources, Oregon grape may have sedative effects. The extent of interaction with antianxiety agents is unknown.
  • Vitamin BVitamin B: According to secondary sources, high doses of Oregon grape may alter the metabolism of vitamin B.
  • Oregon grape/Food Interactions:

  • Insufficient available evidence.
  • Oregon grape/Lab Interactions:

  • BilirubinBilirubin: In animal and in vitro study, berberine, a constituent of Oregon grape, increased bilirubin levels (1).
  • Immune panelImmune panel: In vitro, crude extracts and alkaloid fractions obtained from Mahonia aquifolium have shown immunomodulatory activity (18; 19). The exact effects on the immune system are unclear.