Ephedrine: From Ancient Remedy to Advances in High-Purity Synthesis and Forensic Identification
International Journal of Medical Toxicology and Forensic Medicine,
Vol. 16 (2026),
1 January 2026,
Page 1-8
https://doi.org/10.22037/ijmtfm.v16.50508
Background: Ephedrine, the alkaloid of Ephedra (mainly Ephedra sinica, or Ma Huang), has been utilized in traditional Chinese medicine for decades to treat colds, bronchitis, and asthma due to its sympathomimetic and bronchodilator properties. The isolation of Ephedrine in the late 19th century was a milestone in the field of natural product pharmacology. It was first discovered in Western medicine as an orally active adrenergic receptor agonist. Although therapeutically beneficial, Ephedrine is also associated with dose-related toxicities that range from a mild manifestation such as restlessness and insomnia to serious cardiovascular and neurological adverse effects like hypertension, arrhythmias, seizures, and sudden death. In addition, its use as a precursor to illicit methamphetamine manufacture has contributed to control and public health problems.
Methods: A certified analytical procedure was established that combined FTIR and ¹H-NMR spectroscopy for the authentication of the structure and purity assessment of the analgesic drug ephedrine. In ¹HNMR spectroscopy, the main goal was the assignment of typical environments for protons in the molecule in an effort to ensure the molecular structure is not compromised. The other technique used was FTIR spectroscopy, which aimed to produce a fingerprint of the functional groups.
Results: The ¹H-NMR spectrum of Ephedrine displayed well-resolved and characteristic resonances at δ 7.0–7.4 ppm corresponding to aromatic protons, δ 4.7–5.0 ppm attributed to the hydroxyl (–OH) proton, δ 3.2–3.5 ppm for the methine proton adjacent to the hydroxyl group (–CHOH), and δ 1.0–1.2 ppm corresponding to the methyl group. The absence of extraneous signals confirmed high chemical purity and structural integrity of the sample.
Conclusion: Current analytical advances have enhanced the certainty of ephedrine identification. Fourier-transform infrared spectroscopy (FTIR) provides a rapid structural fingerprint and practical purity assessment. In contrast, proton nuclear magnetic resonance (¹H-NMR) provides detailed information on molecular structure, enabling accurate assignment of functional groups and stereochemistry. Applied in combination, these techniques form a complementary analytical platform for forensic and clinical confirmation of Ephedrine in complex matrices. Concurrently, modern synthetic methodologies maximize enantioselectivity, high yield, and environmental benignity, thereby extending both pharmacological use and forensic discrimination. Therefore, Ephedrine is an exemplar of the dual nature of natural products: an ancient medicine of immense therapeutic utility that, in the twentieth century, has also come to be associated with toxicological hazard, regulatory control, and societal harm.