Mechanism, research progress and warning of the effects of acupuncture at Zusanli point (ST36) on pharmacokinetics: A review

In traditional Chinese medicine, acupuncture is considered free of harmful side effects when properly performed. Pharmacokinetics provides a valuable approach to explore how acupuncture influences drug disposition. Stimulation at specific acupoints, such as Zusanli (ST36), may modulate drug absorption and action. While most studies highlight beneficial outcomes, potential risks also deserve consideration. A systematic review was conducted to evaluate how acupuncture or electroacupuncture at ST36 affects the pharmacokinetics of various drugs. Data on changes in absorption, distribution, metabolism, and excretion, along with pharmacokinetic parameters (e.g., average plasma concentration-time curve [AUC], Cmax, Tmax), were extracted and analyzed. Acupuncture at ST36 significantly influenced the pharmacokinetics of several compounds. For instance, it enhanced the absorption and plasma levels of Schisandra chinensis lignans and acetaminophen (APAP), increasing AUC and Cmax while shortening Tmax. Tissue distribution also shifted, with elevated concentrations observed in certain organs such as the lungs. While aspirin metabolism remained unaffected, ST36 stimulation delayed APAP clearance at higher doses, resulting in prolonged systemic exposure. In the case of triptolide, a bioactive diterpenoid, acupuncture increased its plasma levels and AUC. Some studies reported changes in biomarkers associated with liver function under elevated compound exposure, though no acute adverse effects were noted for commonly used agents. ST36 acupuncture can alter drug pharmacokinetics, potentially impacting drug exposure and clinical response. Awareness of such interactions is important when combining acupuncture with medication. Further studies are warranted to ensure the safe and effective integration of acupuncture into pharmacological treatment strategies.