Seville (sour) Orange Juice: Synephrine Content and Cardiovascular Effects in Normotensive Adults

@article{Penzak2001SevilleO,
  title={Seville (sour) Orange Juice: Synephrine Content and Cardiovascular Effects in Normotensive Adults},
  author={Scott R. Penzak and Michael W. Jann and Julie A. Cold and Yuen Yi Hon and Hiral D. Desai and Bill J Gurley},
  journal={The Journal of Clinical Pharmacology},
  year={2001},
  volume={41}
}
The Seville orange extract Citrus aurantium contains m‐synephrine (phenylephrine) and octopamine; it causes cardiac disturbances in animals and is used by humans for weight loss. Juice from the orange (Seville orange juice [SOJ]) is used to “knock out” intestinal cytochrome P450 (CYP) 3A4 in bioavailability studies. The purpose of this study was to determine synephrine and octopamine concentrations in SOJ and SOJ's cardiovascular effects in normotensive humans. Subjects consumed 8 ounces of SOJ… 
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Safety, Efficacy, and Mechanistic Studies Regarding Citrus aurantium (Bitter Orange) Extract and p‐Synephrine
  • S. Stohs
  • Biology
    Phytotherapy research : PTR
  • 2017
TLDR
This review, as well as several other assessments published in recent years, has concluded that bitter orange extract and p‐synephrine are safe for use in dietary supplements and foods at the commonly used doses.
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