Comparative Review of Essential Oil Mechanisms and Clinical Evidence for Primary Dysmenorrhea Cramp Management

[Objective] This study aimed to compare the pharmacological mechanisms, clinical evidence, and therapeutic potential of essential oils used for the management of primary dysmenorrhea and to identify the most promising candidates for evidence-based complementary therapy. [Methodology] A systematic literature review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. Literature published between 2021 and 2026 was retrieved from three international databases. After duplicate removal and eligibility assessment based on predefined inclusion criteria, 25 studies were included for qualitative synthesis. Data were extracted on study characteristics, essential oil type, active compounds, pharmacological mechanisms, administration methods, intervention duration, and clinical outcomes. The findings were synthesized through a comparative narrative analysis according to mechanism of action, effectiveness, safety profile, and strength of clinical evidence. [Results] The reviewed essential oils consistently demonstrated anti-inflammatory, analgesic, antispasmodic, and neuromodulatory activities that contributed to reducing menstrual pain and improving associated symptoms. Comparative analysis showed that ginger presented the strongest overall potential because of its multiple pharmacological targets, consistent clinical effectiveness, wide availability, and affordability. Peppermint exhibited rapid analgesic and antispasmodic effects, whereas lavender showed the most consistent clinical evidence together with relaxation and anxiolytic benefits. Other essential oils, including cinnamon, chamomile, bergamot, clary sage, and rose, also demonstrated promising therapeutic effects, although supporting evidence was comparatively limited. [Conclusions] Essential oils represent promising complementary interventions for primary dysmenorrhea. However, standardized clinical studies with larger populations are still required to strengthen the evidence and support broader clinical application.