L-arginine - Conjugated Estrogens, Methyltestosterone Interaction
Herbal: L-arginine
Also Known As: 2-Amino-5-guanidinopentanoic acid
Drug: Conjugated Estrogens, Methyltestosterone
Brand names:
Premarin with Methyltestosterone
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 11, 2025
Interaction Details
Conjugated Estrogens, Methyltestosterone is classified as belonging to the following category: Testosterone
Theoretically, concomitant use of L-arginine and testosterone might have additive effects.
In clinical research, L-arginine increases the level of testosterone in male patients with erectile dysfunction. The clinical significance of this finding is unclear.
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
- El Taieb M, Hegazy E, Ibrahim A. Daily oral l-arginine plus tadalafil in diabetic patients with erectile dysfunction: A double-blinded, randomized, controlled clinical trial. J Sex Med. 2019;16(9):1390-1397.
- Abu El-Hamd M, Hegazy EM. Comparison of the clinical efficacy of daily use of L-arginine, tadalafil and combined L-arginine with tadalafil in the treatment of elderly patients with erectile dysfunction. Andrologia. 2020;52(7):e13640.
L-arginine Overview
L-arginine is a naturally occurring amino acid that is involved in a number of important physiological processes, including the production of proteins and the synthesis of nitric oxide, a molecule that helps to relax and widen blood vessels, which can improve blood flow and reduce blood pressure.
The vasodilating effects of L-arginine, and subsequent nitric oxide production, makes it a popular dietary supplement for a variety of conditions, including high blood pressure and erectile dysfunction. It is also commonly used to improve athletic performance.
L-arginine - More Interactions
L-arginine interacts with 398 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.
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