Nutritional Supplement
St. John’s Wort
Negative Interactions
51- Potential Negative Interaction
St. John’s Wort
Alprazolam
St. John's wort increases the activity of an enzyme in the body that metabolizes alprazolam. Consequently, supplementation with St. John's wort may increase the metabolism of, and therefore reduce the activity of, alprazolam.AlprazolamSt. John’s Wort- Roby CA, Anderson GD, Kantor E, et al. St John's Wort: effect on CYP3A4 activity. Clin Pharmacol Ther 2000;67:451-7.
- Potential Negative Interaction
St. John’s Wort
Amitriptyline
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
AmitriptylineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Amoxapine
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
AmoxapineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Chlordiazepoxide
In a study of healthy volunteers, administration of St. John's wort (Hypericum perforatum) along with alprazolam decreased blood levels of alprazolam, compared with the levels when alprazolam was taken by itself.3 Individuals taking alprazolam should not take St. John's wort without supervision by a doctor.
- Potential Negative Interaction
St. John’s Wort
Clomipramine
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
ClomipramineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Clonazepam
In a study of healthy volunteers, administration of St. John's wort (Hypericum perforatum) along with alprazolam decreased blood levels of alprazolam, compared with the levels when alprazolam was taken by itself.3 Individuals taking alprazolam should not take St. John's wort without supervision by a doctor.
- Potential Negative Interaction
St. John’s Wort
Desipramine
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
DesipramineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Desogestrel-Ethinyl Estradiol
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Desogestrel-Ethinyl EstradiolSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Diazepam
In a study of healthy volunteers, administration of St. John's wort (Hypericum perforatum) along with alprazolam decreased blood levels of alprazolam, compared with the levels when alprazolam was taken by itself.3 Individuals taking alprazolam should not take St. John's wort without supervision by a doctor.
- Potential Negative Interaction
St. John’s Wort
Doxepin
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
DoxepinSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Estazolam
In a study of healthy volunteers, administration of St. John's wort (Hypericum perforatum) along with alprazolam decreased blood levels of alprazolam, compared with the levels when alprazolam was taken by itself.3 Individuals taking alprazolam should not take St. John's wort without supervision by a doctor.
- Potential Negative Interaction
St. John’s Wort
Ethinyl Estradiol and Levonorgestrel
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Ethinyl Estradiol and LevonorgestrelSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Ethinyl Estradiol and Norethindrone
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Ethinyl Estradiol and NorethindroneSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Ethinyl Estradiol and Norgestimate
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Ethinyl Estradiol and NorgestimateSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Ethinyl Estradiol and Norgestrel
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Ethinyl Estradiol and NorgestrelSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Fluvoxamine
One report describes a case of serotonin syndrome in a patient who took St. John’s wort and trazodone, a weak SSRI drug. The patient experienced mental confusion, muscle twitching, sweating, flushing, and ataxia. In another case, a patient experienced grogginess, lethargy, nausea, weakness, and fatigue after taking one dose of paroxetine (Paxil®, an SSRI drug related to fluvoxamine) after ten days of St. John’s wort. Until more is known about interactions and adverse actions, people taking any SSRI drugs, including fluvoxamine, should avoid St. John’s wort, unless they are being closely monitored by a doctor.
FluvoxamineSt. John’s Wort- Demott K. St. John's wort tied to serotonin syndrome. Clinical Psychiatry News 1998;26:28.
- Gordon JB. SSRIs and St. John's wort: possible toxicity? Am Fam Physician 1998;57:950.
- Potential Negative Interaction
St. John’s Wort
Imipramine Pamoate
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
Imipramine PamoateSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Levonorgestrel
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
LevonorgestrelSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Levonorgestrel-Ethinyl Estrad
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Levonorgestrel-Ethinyl EstradSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Lorazepam
In a study of healthy volunteers, administration of St. John's wort (Hypericum perforatum) along with alprazolam decreased blood levels of alprazolam, compared with the levels when alprazolam was taken by itself.3 Individuals taking alprazolam should not take St. John's wort without supervision by a doctor.
- Potential Negative Interaction
St. John’s Wort
Mestranol and Norethindrone
Cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Mestranol and NorethindroneSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Nefazodone
Although there have been no interactions reported in the medical literature, it is best to avoid using nefazodone with St. John’s wort unless you are under the supervision of a qualified healthcare professional.
- Potential Negative Interaction
St. John’s Wort
Norgestimate-Ethinyl Estradiol
Eight cases reported to the Medical Products Agency of Sweden suggest that St. John’s wort may interact with oral contraceptives and cause intramenstrual bleeding and/or changes in menstrual bleeding. One reviewer has suggested that St. John’s wort may reduce serum levels of estradiol. It should be noted, however, that only three of the eight Swedish women returned to normal menstrual cycles after stopping St. John’s wort. Women taking oral contraceptives for birth control should consult with their doctor before taking St. John’s wort.
Norgestimate-Ethinyl EstradiolSt. John’s Wort- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Potential Negative Interaction
St. John’s Wort
Nortriptyline
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
NortriptylineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Paroxetine
One report described a case of serotonin syndrome in a patient who took St. John’s wort and trazodone, a weak SSRI drug. The patient reportedly experienced mental confusion, muscle twitching, sweating, flushing, and ataxia. In another case, a patient experienced grogginess, lethargy, nausea, weakness, and fatigue after taking one dose of paroxetine after ten days of St. John’s wort use.
ParoxetineSt. John’s Wort- Demott K. St. John's wort tied to serotonin syndrome. Clinical Psychiatry News 1998;26:28.
- Gordon JB. SSRIs and St. John's wort: possible toxicity? Am Fam Physician 1998;57:950.
- Potential Negative Interaction
St. John’s Wort
Paroxetine Mesylate
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
There have been no published reports about negative consequences of combining St. John’s wort (Hypericum perforatum) (Hypericum perforatum) (Hypericum perforatum) and fluoxetine. One case has been reported of an interaction between St. John’s wort and a weak serotonin reuptake inhibitor drug known as trazodone that is vaguely similar to fluoxetine. In another case, a patient experienced grogginess, lethargy, nausea, weakness, and fatigue after taking one dose of paroxetine (Paxil®, another SSRI drug) after ten days of St. John’s wort use. Nevertheless, some doctors are concerned about the possibility of an interaction between St. John’s wort and fluoxetine causing side effects (e.g., mental confusion, muscle twitching, sweating, flushing) known collectively as serotonin syndrome. Until more is known about interactions and adverse actions, people taking any SSRI drugs, including fluoxetine, should avoid St. John’s wort, unless they are being closely monitored by a doctor.
Paroxetine MesylateSt. John’s Wort- Demott K. St. John's wort tied to serotonin syndrome. Clinical Psychiatry News 1998;26:28.
- Gordon JB. SSRIs and St. John's wort: possible toxicity? Am Fam Physician 1998;57:950.
- Bekman SE, Sommi RW, Switzer J. Consumer sue of St. John's wort: A survey on effectiveness, safety, and tolerability. Pharmacotherapy 2000;20:568-74.
- Lantz MS, Buchalter E, Giambanco V. St. John's wort and antidepressant drug interaction in the elderly. J Geriatr Psychiatry Neurol 1999;12:7-10.
- Potential Negative Interaction
St. John’s Wort
Phenelzine
Although St. John’s wort contains chemicals that bind MAO in test tubes, it is believed that the action of St. John’s wort is not due to MAOI activity. However, because St. John’s wort may have serotonin reuptake inhibiting action (similar to the action of drugs such as Prozac®, it is best to avoid concomitant use of St. John’s wort with MAOI drugs.
PhenelzineSt. John’s Wort- St. John's wort, Hypericum perforatum. In American Herbal Pharmacopoeia and Therapeutic Compendium, ed. R Upton. Santa Cruz, CA: AHP, 1997.
- Potential Negative Interaction
St. John’s Wort
Protriptyline
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
ProtriptylineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Sertraline
One report described a case of serotonin syndrome in a patient who took St. John’s wort and trazodone, a weak SSRI drug. The patient reportedly experienced mental confusion, muscle twitching, sweating, flushing, and ataxia. In another case, a patient experienced grogginess, lethargy, nausea, weakness, and fatigue after taking one dose of paroxetine (Paxil®, another SSRI drug) after ten days of St. John’s wort use.
SertralineSt. John’s Wort- Demott K. St. John's wort tied to serotonin syndrome. Clinical Psychiatry News 1998;26:28.
- Gordon JB. SSRIs and St. John's wort: possible toxicity? Am Fam Physician 1998;57:950.
- Potential Negative Interaction
St. John’s Wort
Temazepam
In a study of healthy volunteers, administration of St. John's wort (Hypericum perforatum) along with alprazolam decreased blood levels of alprazolam, compared with the levels when alprazolam was taken by itself.3 Individuals taking alprazolam should not take St. John's wort without supervision by a doctor.
- Potential Negative Interaction
St. John’s Wort
Trazodone
One report described a case of serotonin syndrome in a patient who took St. John’s wort and trazodone. The patient reportedly experienced mental confusion, muscle twitching, sweating, flushing, and ataxia. Until more is known, St. John’s wort should not be combined with trazodone except under expert clinical supervision.
TrazodoneSt. John’s Wort- Demott K. St. John's wort tied to serotonin syndrome. Clinical Psychiatry News 1998;26:28.
- Potential Negative Interaction
St. John’s Wort
Trimipramine
Preliminary research has suggested that St. John’s wort (Hypericum perforatum) may reduce blood levels of the tricyclic antidepressant amitriptyline. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking tricyclic antidepressants should avoid St. John’s wort.
TrimipramineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Potential Negative Interaction
St. John’s Wort
Venlafaxine
Although there have been no interactions reported in the medical literature, it is best to avoid using venlafaxine with St. John’s wort unless you are under the supervision of a qualified healthcare professional.
- Reduces Effectiveness
St. John’s Wort
Amprenavir
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Studies have shown that taking indinavir together with St. John’s wort results in increased breakdown and dramatically reduced blood levels of indinavir. Therefore, people taking indinavir should not take St. John’s wort.
Indinavir is a protease inhibitor used to treat people with HIV infection. A pharmacological study gave indinavir to healthy volunteers for two days. On day 3, volunteers added 900 mg of St. John’s wort extract per day. At the end of the study, it was found that St. John’s wort led to a significant reduction in serum levels of indinavir. Until more is known, people taking indinavir or other antiretroviral drugs for HIV infection should avoid using St. John’s wort.
AmprenavirSt. John’s Wort- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet 2000;355:547-8 [letter].
- Moore LB, Goodwin B, Jones SA, et al. St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proc Natl Acad Sci USA 2000;97:7500-2.
- Reduces Effectiveness
St. John’s Wort
Atazanavir
Taking St. John’s wort (Hypericum perforatum) when taking atazanavir might result in reduced blood levels of the drug, which could lead to reduced effectiveness and eventual resistance. Individuals taking atazanavir should avoid taking St. John’s wort at the same time.
- Reduces Effectiveness
St. John’s Wort
Atazanavir-Cobicistat
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Studies have shown that taking indinavir together with St. John’s wort results in increased breakdown and dramatically reduced blood levels of indinavir. Therefore, people taking indinavir should not take St. John’s wort.
Indinavir is a protease inhibitor used to treat people with HIV infection. A pharmacological study gave indinavir to healthy volunteers for two days. On day 3, volunteers added 900 mg of St. John’s wort extract per day. At the end of the study, it was found that St. John’s wort led to a significant reduction in serum levels of indinavir. Until more is known, people taking indinavir or other antiretroviral drugs for HIV infection should avoid using St. John’s wort.
Atazanavir-CobicistatSt. John’s Wort- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet 2000;355:547-8 [letter].
- Moore LB, Goodwin B, Jones SA, et al. St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proc Natl Acad Sci USA 2000;97:7500-2.
- Reduces Effectiveness
St. John’s Wort
Atorvastatin
St. John's wort increases the activity of an enzyme in the body that metabolizes atorvastatin . Consequently, supplementation with St. John's wort may increase the metabolism of, and therefore reduce the activity of, atorvastatin.AtorvastatinSt. John’s Wort- Roby CA, Anderson GD, Kantor E, et al. St John's Wort: effect on CYP3A4 activity. Clin Pharmacol Ther 2000;67:451-7.
- Reduces Effectiveness
St. John’s Wort
Cyclosporine
Pharmacological research from Europe suggests that St. John’s wort (Hypericum perforatum) may reduce plasma levels of cyclosporine. Two case reports also describe heart transplant patients taking cyclosporine who showed signs of acute transplant rejection after taking St. John’s wort extract. In both cases, reduced plasma concentrations of cyclosporine were found. One report cites similar findings in three patients taking cyclosporine and St. John’s wort together. Finally, similar drops in cyclosporine blood levels were reported in 45 kidney or liver transplant patients who began taking St. John’s wort. Until more is known, people taking cyclosporine should avoid the use of St. John’s wort.
CyclosporineSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Rauschitzka F, Meir P, Turina M, et al. Acute transplant rejection due to Saint John's wort. Lancet 2000;355:548-9 [letter].
- Ernst E. Second thoughts about safety of St. John's wort. Lancet 1999;354:2014-6 [letter].
- Breidenbach T, Hoffmann MW, Becker T, et al. Drug interaction of St. John's wort with ciclopsorin. Lancet 2000;355:1912 [letter].
- Reduces Effectiveness
St. John’s Wort
Digoxin
One preliminary trial has suggested that St. John’s wort(Hypericum perforatum) may reduce blood levels of digoxin. In this study, healthy volunteers took digoxin for five days, after which they added 900 mg per day of St. John’s wort while continuing the daily digoxin. A normal blood level of digoxin was reached after five days of taking the drug, but this level dropped significantly when St. John’s wort was added. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking digoxin should avoid St. John’s wort.
DigoxinSt. John’s Wort- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Reduces Effectiveness
St. John’s Wort
Fosamprenavir
Taking St. John’s wort (Hypericum perforatum) when taking fosamprenavir might result in reduced blood levels of the drug, which could lead to reduced effectiveness and eventual resistance. Individuals taking fosamprenavir should avoid taking St. John’s wort at the same time.
- Reduces Effectiveness
St. John’s Wort
Indinavir
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Studies have shown that taking indinavir together with St. John’s wort results in increased breakdown and dramatically reduced blood levels of indinavir. Therefore, people taking indinavir should not take St. John’s wort.
Indinavir is a protease inhibitor used to treat people with HIV infection. A pharmacological study gave indinavir to healthy volunteers for two days. On day 3, volunteers added 900 mg of St. John’s wort extract per day. At the end of the study, it was found that St. John’s wort led to a significant reduction in serum levels of indinavir. Until more is known, people taking indinavir or other antiretroviral drugs for HIV infection should avoid using St. John’s wort.
IndinavirSt. John’s Wort- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet 2000;355:547-8 [letter].
- Moore LB, Goodwin B, Jones SA, et al. St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proc Natl Acad Sci USA 2000;97:7500-2.
- Reduces Effectiveness
St. John’s Wort
Ketamine
Ketamine is given primarily by injection as an anesthetic and to relieve pain. It can also be used orally to treat chronic pain. In a study of healthy volunteers, administration of St. John's wort along with ketamine, decreased blood levels of the drug, which suggests that St. John's wort would decrease the effectiveness of orally administered ketamine.KetamineSt. John’s Wort- Peltoniemi MA, Saari TI, Hagelberg NM, et al. St John's wort greatly decreases the plasma concentrations of oral S-ketamine. Fundam Clin Pharmacol 2012;26:743-50.
- Reduces Effectiveness
St. John’s Wort
Lovastatin
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
St. John's wort increases the activity of an enzyme in the body that metabolizes lovastatin . Consequently, supplementation with St. John's wort may increase the metabolism of, and therefore reduce the activity of, lovastatin.LovastatinSt. John’s Wort- Roby CA, Anderson GD, Kantor E, et al. St John's Wort: effect on CYP3A4 activity. Clin Pharmacol Ther 2000;67:451-7.
- Reduces Effectiveness
St. John’s Wort
Nelfinavir
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Studies have shown that taking indinavir together with St. John’s wort results in increased breakdown and dramatically reduced blood levels of indinavir. Therefore, people taking indinavir should not take St. John’s wort.
Indinavir is a protease inhibitor used to treat people with HIV infection. A pharmacological study gave indinavir to healthy volunteers for two days. On day 3, volunteers added 900 mg of St. John’s wort extract per day. At the end of the study, it was found that St. John’s wort led to a significant reduction in serum levels of indinavir. Until more is known, people taking indinavir or other antiretroviral drugs for HIV infection should avoid using St. John’s wort.
NelfinavirSt. John’s Wort- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet 2000;355:547-8 [letter].
- Moore LB, Goodwin B, Jones SA, et al. St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proc Natl Acad Sci USA 2000;97:7500-2.
- Reduces Effectiveness
St. John’s Wort
Omeprazole
In a study of healthy human volunteers, supplementing with St. John's wort greatly decreased omeprazole blood levels by accelerating the metabolism of the drug. Use of St. John's wort may, therefore, interfere with the actions of omeprazole.
OmeprazoleSt. John’s Wort- Wang LS, Zhou G, Zhu B, et al. St John's wort induces both cytochrome P450 3A4-catalyzed sulfoxidation and 2C19-dependent hydroxylation of omeprazole. Clin Pharmacol Ther 2004;75:191-7.
- Reduces Effectiveness
St. John’s Wort
Ritonavir
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Studies have shown that taking indinavir together with St. John’s wort results in increased breakdown and dramatically reduced blood levels of indinavir. Therefore, people taking indinavir should not take St. John’s wort.
Indinavir is a protease inhibitor used to treat people with HIV infection. A pharmacological study gave indinavir to healthy volunteers for two days. On day 3, volunteers added 900 mg of St. John’s wort extract per day. At the end of the study, it was found that St. John’s wort led to a significant reduction in serum levels of indinavir. Until more is known, people taking indinavir or other antiretroviral drugs for HIV infection should avoid using St. John’s wort.
RitonavirSt. John’s Wort- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet 2000;355:547-8 [letter].
- Moore LB, Goodwin B, Jones SA, et al. St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proc Natl Acad Sci USA 2000;97:7500-2.
- Reduces Effectiveness
St. John’s Wort
Saquinavir
This interaction is based on this drug belonging to a drug class. While this drug may differ from the text and references below, drugs within this class work in a similar way and this interaction is applicable to drugs within the same class.
Studies have shown that taking indinavir together with St. John’s wort results in increased breakdown and dramatically reduced blood levels of indinavir. Therefore, people taking indinavir should not take St. John’s wort.
Indinavir is a protease inhibitor used to treat people with HIV infection. A pharmacological study gave indinavir to healthy volunteers for two days. On day 3, volunteers added 900 mg of St. John’s wort extract per day. At the end of the study, it was found that St. John’s wort led to a significant reduction in serum levels of indinavir. Until more is known, people taking indinavir or other antiretroviral drugs for HIV infection should avoid using St. John’s wort.
SaquinavirSt. John’s Wort- Piscitelli SC, Burstein AH, Chaitt D, et al. Indinavir concentrations and St. John's wort. Lancet 2000;355:547-8 [letter].
- Moore LB, Goodwin B, Jones SA, et al. St. John's wort induces hepatic drug metabolism through activation of the pregnane X receptor. Proc Natl Acad Sci USA 2000;97:7500-2.
- Reduces Effectiveness
St. John’s Wort
Simvastatin
In patients taking simvastatin, treatment with St. John's wort increased serum cholesterol levels, apparently because St. John's wort interfered with the effect of the medication.SimvastatinSt. John’s Wort- Eggertsen R, Andreasson A, Andren L. Effects of treatment with a commercially available St John's Wort product (Movina) on cholesterol levels in patients with hypercholesterolemia treated with simvastatin. Scand J Prim Health Care 207;25:154-9.
- Reduces Effectiveness
St. John’s Wort
Theophylline
One case study of a 42-year old asthmatic woman reported that taking 300 mg per day of St. John’s wort extract led to a significant decrease in blood levels of theophylline. Following discontinuation of St. John’s wort, the patient’s blood levels of theophylline returned to an acceptable therapeutic level. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. Until more is known, people taking theophylline should avoid St. John’s wort.
TheophyllineSt. John’s Wort- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Reduces Effectiveness
St. John’s Wort
Warfarin
According to a preliminary report, volunteers taking 900 mg per day of St. John’s wort were given a single dose of an anticoagulant similar in action to warfarin. There was a significant drop in the amount of the drug measured in the blood. Seven case studies reported to the Medical Products Agency in Sweden also found a decrease in the anticoagulant activity of warfarin when St. John’s wort was taken at the same time. This may have occurred because certain chemicals found in St. John’s wort activate liver enzymes that are involved in the elimination of some drugs. People taking warfarin should consult with their doctor before taking St. John’s wort.
WarfarinSt. John’s Wort- Mauer A, Johne A, Bauer S, et al. Interaction of St. John's wort extract with phenprocoumon [abstract]. Eur J Clin Pharmacol 1999;55:A22.
- Safety of St. John's wort (Hypericum perforatum) [letters to the editor from various authors]. Lancet 2000;355:575-7.
- Nebel A, Schneider BJ, Baker RK, Kroll DJ. Potential metabolic interaction between St. John's wortand theophylline [letter]. Ann Pharmacother 1999;33:502.
- Mai I, Schmider J, et al. Unpublished results, May, 1999. Reported in: Johne A, Brockmöller, Bauer S, et al. Pharmacokinetic interaction of digoxin with an herbal extract from St. John's wort (Hypericum perforatum). Clin Pharmacol Ther 1999;66:338-45.
- Reduces Effectiveness
St. John’s Wort
Zolpidem
In healthy volunteers, supplementation with St. John's wort (Hypericum perforatum) along with zolpidem decreased blood levels of zolpidem, apparently by accelerating the metabolism of the drug.ZolpidemSt. John’s Wort- Hojo Y, Echizenya M, Ohkubo T, Shimizu T. Drug interaction between St John's wort and zolpidem in healthy subjects. J Clin Pharm Ther 2011;36:711-5.
Explanation Required
1- Needs Explanation
St. John’s Wort
Fexofenadine
In a study of healthy volunteers, administration of 900 mg of St. John's wort one hour prior to fexofenadine resulted in a significant increase in blood levels of fexofenadine, compared with the blood levels after taking fexofenadine alone. On the other hand, long-term administration of St. John's wort (300 mg three times per day for two weeks) did not alter blood levels of fexofenadine. Until more is known, St. John's wort should not be combined with fexofenadine, except under the supervision of a doctor.
FexofenadineSt. John’s Wort- Wang Z, Hamman MA, Huang SM, et al. Effect of St John's wort on the pharmacokinetics of fexofenadine. Clin Pharmacol Ther2002;71:414-20.