Oxedrine (-)- is an inactive enantiomer of alkaloid oxedrine (synephrine). Oxedrine (-)- was detected in orange juice and marmalade. It may thus possibly be formed during production using citrus fruits. The natural alkaloid synephrine exists only as (+)-synephrine, whereas synthetically produced synephrine exists as a 50/50 racemic mixture of (-)/(+)-synephrine. Following ingestion of (+)-oxedrine, it is postulated that chiral inversion occurs, resulting in inversion to oxedrine (-)- in urine. Epinephrine analogs such as propadrine and oxedrine (-)- counteracted the biological action of epinephrine.