Licorice - Conjugated Estrogens, Methyltestosterone Interaction
Herbal: Licorice
Also Known As: Glycyrrhiza echinate, Alcacuz, Bois Doux, Can Cao, Deglycyrrhized Licorice, Gan Cao, Gan Zao, Glabra, Glycyrrhizic Acid, Glycyrrhizinic Acid, Kanzo, Lakritze, Liquiritiae Radix, Liquirizia, Mulathi, Mulethi, Orozuz, Subholz, Yashtimadhu, Yashti-Madhu
Drug: Conjugated Estrogens, Methyltestosterone
Brand names:
Premarin with Methyltestosterone
![](https://hellopharmacist.nyc3.digitaloceanspaces.com/images/OBrXo3ni0aNq6p1xr8LXWNogoaVtCExyhTj9MEzw.jpg)
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Jun 02, 2024
Interaction Details
Conjugated Estrogens, Methyltestosterone is classified as belonging to the following category: Cytochrome P450 3A4 (Cyp3A4) Substrates
Theoretically, licorice might increase or decrease levels of drugs metabolized by CYP3A4.
Pharmacokinetic research shows that the licorice constituent glycyrrhizin, taken in a dosage of 150 mg orally twice daily for 14 days, modestly decreases the area under the concentration-time curve of midazolam by about 20%. Midazolam is a substrate of CYP3A4, suggesting that glycyrrhizin modestly induces CYP3A4 activity. Animal research also shows that licorice extract from the species G. uralensis induces CYP3A4 activity. However, licorice extract from G. glabra species appear to inhibit CYP3A4-induced metabolism of testosterone in vitro. It is thought that the G. glabra inhibits CYP3A4 due to its constituent glabridin, which is a moderate CYP3A4 inhibitor in vitro and not present in other licorice species. Until more is known, licorice should be used cautiously in people taking CYP3A4 substrates.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Kent UM, Aviram M, Rosenblat M, Hollenberg PF. The licorice root derived isoflavan glabridin inhibits the activities of human cytochrome P450S 3A4, 2B6, and 2C9. Drug Metab Dispos 2002;30:709-15..
- Mu Y, Zhang J, Zhang S, et al. Traditional Chinese medicines Wu Wei Zi (Schisandra chinensis Baill) and Gan Cao (Glycyrrhiza uralensis Fisch) activate pregnane X receptor and increase warfarin clearance in rats. J Pharmacol Exp Ther 2006;316:1369-77.
- Tu, J. H., He, Y. J., Chen, Y., Fan, L., Zhang, W., Tan, Z. R., Huang, Y. F., Guo, D., Hu, D. L., Wang, D., and Hong-Hao Zhou. Effect of glycyrrhizin on the activity of CYP3A enzyme in humans. Eur J Clin Pharmacol 2010;66(8):805-810.
- Li G, Simmler C, Chen L, et al. Cytochrome P450 inhibition by three licorice species and fourteen licorice constituents. Eur J Pharm Sci. 2017;109:182-190.
Interaction Details
Conjugated Estrogens, Methyltestosterone is classified as belonging to the following category: Estrogens
Theoretically, licorice might increase or decrease the effects of estrogen therapy.
Theoretically, licorice might interfere with estrogen therapy due to estrogenic and anti-estrogenic effects.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Amato P, Christophe S, Mellon PL. Estrogenic activity of herbs commonly used as remedies for menopausal symptoms. Menopause 2002;9:145-50.
- Francini-Pesenti F, Puato M, Piccoli A, Brocadello F. Liquorice-induced hypokalaemia and water retention in the absence of hypertension. Phytother Res 2008;22:563-5.
Interaction Details
Conjugated Estrogens, Methyltestosterone is classified as belonging to the following category: P-Glycoprotein Substrates
Theoretically, licorice might decrease the absorption of P-glycoprotein substrates.
In vitro research shows that licorice can increase P-glycoprotein activity.
Interaction Rating
Likelihood of Occurrence
PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists
References
- Wang H, Dong L, Qu F, et al. Effects of glycyrrhizin on the pharmacokinetics of nobiletin in rats and its potential mechanism. Pharm Biol. 2020 Dec;58(1):352-356.
Licorice Overview
![Licorice](https://hellopharmacist.nyc3.digitaloceanspaces.com/images/herbals/width_250/urrDGrlUD25YUBL7ATUFzhoAwo5u3jjInMaIYT72.jpg)
Licorice - More Interactions
Licorice interacts with 951 drugs
Interaction Rating Key
These severity listings are for informational use only. Never start, stop or otherwise change your therapy before speaking with your provider.
Major | The combined use of these agents is strongly discouraged as serious side effects or other negative outcomes could occur. |
Moderate | Use cautiously under the care of a healthcare professional or avoid this combination. A significant interaction or negative outcome could occur. |
Minor | Be aware that there is a chance of an interaction. Watch for warning signs of a potential interaction. |
Unknown | No interactions have been reported or no interaction data is currently available. |
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Parts of this content are provided by the Therapeutic Research Center, LLC.
DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.
© 2021 Therapeutic Research Center, LLC
Drug descriptions are provided by MedlinePlus.