Bitter Orange - NyQuil (acetaminophen, dextromethorphan, doxylamine) Interaction
Herbal: Bitter Orange
Also Known As: Citrus aurantium, Aurantii Fructus, Aurantium, Bigarade, Chisil, Kijitsu, Marmalade Orange, Meta-Synephrine, Naranja Amarga, Neroli Oil, Norsynephrine, Octopamine, Orange Amère, Seville Orange, Shangzhou Zhiqiao, Sour Orange, Synephrine, Zhi Ke, Zhi Qiao, Zhi Shi
Drug: acetaminophen, dextromethorphan, doxylamine
Brand names:
NyQuil
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
May 25, 2025
Interaction Details
acetaminophen, dextromethorphan, doxylamine is classified as belonging to the following category: Dextromethorphan (Robitussin Dm, Others)
Bitter orange might increase blood levels of dextromethorphan.
One small clinical study shows that bitter orange juice increases dextromethorphan levels, likely through cytochrome P450 3A4 (CYP3A4) inhibition. Theoretically, bitter orange might increase the risk for dextromethorphan-related adverse 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
- Di Marco MP, Edwards DJ, Wainer IW, Ducharme MP. The effect of grapefruit juice and seville orange juice on the pharmacokinetics of dextromethorphan: the role of gut CYP3A and P-glycoprotein. Life Sci 2002;71:1149-60.
Bitter Orange Overview
Bitter orange, also known as Seville orange or sour orange, is a type of citrus fruit that is native to Southeast Asia. It is closely related to the sweet orange, but has a much more bitter and sour flavor.
Bitter orange is a rich source of vitamin C and other nutrients, including calcium, potassium, and folate. It is also a good source of antioxidants.
Bitter orange has been used in traditional medicine for a number of purported health benefits, including improved digestion, improved immune function, and reduced inflammation.
Bitter orange also contains synephrine, a compound similar in structure to ephedrine. Synephrine is thought to have stimulant effects and is often used to increase energy, improve athletic performance, and as a weight loss supplement. When used as a dietary supplement, the dosage is typically standardized by its synephrine content.
Bitter Orange - More Interactions
Bitter Orange interacts with 931 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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Dr. Brian Staiger, PharmD
In addition to being a clinical pharmacist specializing in pharmacotherapy, Dr. Brian Staiger is a registered herbalist through the American Herbalist Guild. He has combined his passion for pharmacy practice with the study of medical ethnobotany to improve patient care. Feel free to reach out about any of your herbal or medication questions!
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