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Testing Status of Bitter orange Extract Mixture M040019



Synonyms/Common Names

  • caffeine
  • Citrus aurantium L. var. amara
  • Synephrine


  • 58-08-2 - Caffeine
  • 94-07-5 - p-Synephrine

Known Uses

Dietary supplement and flavoring in foods and beverages; used in herbal weight loss formulas

Organ Systems Toxicity

  • 3 to 20 GD Conventional Teratology (Gavage)  (TER20502)  Completed 
    • Citation: Deborah K. Hansen, Beth E. Juliar, Gene E. White, and Linda S. Pellicore. Developmental Toxicity of Citrus aurantium (bitter orange) in Rats. Birth Defects Res. (Part B) 92:216-223 (2011)
    • Citation: Hansen DK, George NI, White GE, Abdel-Rahman A, Pellicore LS, Fabricant D. Cardiovascular toxicity of Citrus aurantium in exercised rats. Cardiovasc Toxicol. (3): 208-19. (2013)
    • Citation: Hansen, D.K., George, N.I., White, G.E., Pellicore, L.S., Abdel-Rahman, A., and Fabricant, D. Physiological effects following administration of Citrus aurantium for 28 days in rats. Toxicology and Applied Pharmacology, 261(3), 236-27 (2012).
    • Female Rats: Sprague Dawley
    • Dose: Dose 1: Control vehicle; Dose 2: Bitter Orange (BO) (6% Extract) - 10 MG/KG BWT; Dose 3: BO (6% EXTRACT) - 25 MG/KG BWT; DOSE 4: BO (6% EXTRACT) - 50 MG/KG BWT; DOSE 5: BO (6% EXTRACT) - 100 MG/KG BWT. 25 mg/kg caffeine; 10 mg/kg BO (6% extract) +/- 25 mg/kg caffeine; 50 mg/kg BO (6% extract) +/- 25 mg/kg caffeine; 10 mg/kg synephrine (90% extract) +/- 25 mg/kg caffeine; 50 mg/kg synephrine (90% extract) +/- 25 mg/kg caffeine..