Quick Summary

Bitter Orange (Citrus aurantium) is a botanical source traditionally used in complementary medicine. Research has explored its potential benefits in areas such as anxiety reduction, chemotherapy-induced nausea and vomiting, and women’s health symptoms including dysmenorrhea and menopausal symptoms. Clinical evidence generally involves essential oils and extracts from Citrus aurantium used adjunctively or complementarily, often reporting favorable safety profiles but with limitations in study quality and consistency. Mechanistic and preclinical studies suggest that it contains diverse bioactive compounds with antimicrobial and metabolic regulatory properties. Safety data are incomplete, recommending cautious use, especially in vulnerable populations.

What is it?

Bitter Orange, scientifically known as Citrus aurantium, is a citrus fruit whose extracts and essential oils have been used in traditional and complementary medicine. The essential oils, particularly neroli oil derived from the flowers, are often employed in aromatherapy and topical applications.

Traditional Uses

Traditionally, Bitter Orange has been used for its calming effects, digestive support, and relief of various women’s health issues such as menstrual pain and menopausal discomfort. Aromatherapy with its essential oil is also commonly applied for anxiety and nausea relief.

Active Compounds

Bitter Orange contains multiple bioactive constituents, including:

  • Flavonoids
  • Essential oils such as linalool, limonene, and neroli oil
  • Alkaloids
  • Other phytochemicals with antimicrobial and metabolic effects

Potential Benefits with Evidence Levels

  • Anxiety (Moderate): Randomized controlled trials and systematic reviews suggest aromatherapy using Citrus aurantium essential oil may reduce both state and trait anxiety scores. It is ranked among the most effective essential oils for anxiety reduction (Tan et al. 2023; Yilmaz 2026).
  • Chemotherapy-induced nausea and vomiting (CINV) (Moderate): An RCT in breast cancer patients indicated that inhalation aromatherapy with Citrus aurantium essential oil significantly alleviated delayed-phase chemotherapy-induced nausea and vomiting compared to control (Tabei et al. 2025).
  • Menopausal symptoms (Low to Moderate): Systematic reviews and meta-analyses report aromatherapy including Citrus aurantium reduces physical and psychological menopausal symptoms and improves sleep quality (Karimi et al. 2025).
  • Primary dysmenorrhea and labor pain (Low to Moderate): Neroli essential oil from Citrus aurantium has shown potential in reducing pain and anxiety related to primary dysmenorrhea and labor in randomized controlled trials (Yilmaz 2026).
  • Metabolic parameters and glucose metabolism (Preliminary Clinical Evidence): Some clinical trials of food supplements containing Citrus extracts suggest improvements in glucose metabolism and lipid profiles in subjects with impaired fasting glucose (Di Minno et al. 2025).
  • Antimicrobial and food preservation (Preclinical/In vitro): Citrus aurantium essential oils demonstrate antimicrobial activity against Escherichia coli and potential synergistic effects with other essential oils for food preservation (Ellouze et al. 2024).

Side Effects

  • Mild and infrequent adverse events such as skin irritation from topical or inhaled essential oils have been reported.
  • No severe adverse events were noted in reviewed clinical trials.
  • Cardiovascular toxicity has been observed in animal studies at high doses of Citrus aurantium extracts; however, this has not been confirmed in humans.

Drug Interactions

Currently, no high-quality clinical evidence clearly identifies significant drug interactions with Citrus aurantium. However, due to its bioactive compounds, the possibility of interactions cannot be excluded and further study is warranted.

Who Should Avoid It?

No definitive contraindications have been established based on clinical evidence. Caution is advised for individuals with cardiovascular disorders due to uncertain safety profiles at higher doses. Pregnant and breastfeeding women should use Citrus aurantium with caution and under professional guidance, as limited data exist on safety in these populations. Aromatherapy studies during pregnancy suggest possible benefits without adverse events, but evidence remains insufficient.

Evidence Limitations

  • Many clinical studies feature small sample sizes, short durations, and variable methodologies.
  • Systematic reviews and meta-analyses show significant heterogeneity and sometimes unclear risk of bias.
  • Safety reporting is often incomplete or absent in many trials.
  • The majority of evidence pertains to essential oil aromatherapy rather than whole herb consumption.
  • Preclinical and in vitro findings may not directly translate to clinical effects.
  • High-quality, large-scale randomized controlled trials are needed to confirm efficacy and safety for specific uses.

References

Last Reviewed

June 2024

Information Disclaimer: This content is for informational purposes only and is not intended as medical advice. Bitter Orange and its derivatives may have potential effects that require further research and confirmation. Always consult a qualified healthcare professional before starting any new treatment, especially if you have underlying health conditions or are taking medications.