BACKGROUNDObservational studies from Asia suggest that maxingshigan-yinqiaosan may be effective in the treatment of acute H1N1 influenza.OBJECTIVETo compare the efficacy and safety of oseltamivir and maxingshigan-yinqiaosan in treating uncomplicated H1N1 influenza.DESIGNProspective, nonblinded, randomized, controlled trial. (ClinicalTrials.gov registration number: NCT00935194)SETTINGEleven hospitals from 4 provinces in China.PATIENTS410 persons [corrected] aged 15 to 69 [corrected] years with laboratory-confirmed H1N1 influenza.INTERVENTIONOseltamivir, 75 mg twice daily; maxingshigan-yinqiaosan decoction (composed of 12 Chinese herbal medicines, including honey-fried Herba Ephedrae), 200 mL 4 times daily; oseltamivir plus maxingshigan-yinqiaosan; or no intervention (control). Interventions and control were given for 5 days.MEASUREMENTSPrimary outcome was time to fever resolution. Secondary outcomes included symptom scores and viral shedding determined by using real-time reverse transcriptase polymerase chain reaction.RESULTSSignificant reductions in the estimated median time to fever resolution compared with the control group (26.0 hours [95% CI, 24.0 to 33.0 hours]) were seen with oseltamivir (34% [95% CI, 20% to 46%]; P < 0.001), maxingshigan-yinqiaosan (37% [CI, 23% to 49%]; P < 0.001), and oseltamivir plus maxingshigan-yinqiaosan (47% [CI, 35% to 56%]; P < 0.001). Time to fever resolution was reduced by 19% (CI, 0.3% to 34%; P = 0.05) with oseltamivir plus maxingshigan-yinqiaosan compared with oseltamivir. The interventions and control did not differ in terms of decrease in symptom scores (P = 0.38). Two patients who received maxingshigan-yinqiaosan reported nausea and vomiting.LIMITATIONSParticipants were young and had mild H1N1 influenza virus infection. Missing viral data precluded definitive conclusions about viral shedding.CONCLUSIONOseltamivir and maxingshigan-yinqiaosan, alone and in combination, reduced time to fever resolution in patients with H1N1 influenza virus infection. These data suggest that maxingshigan-yinqiaosan may be used as an alternative treatment of H1N1 influenza virus infection.PRIMARY FUNDING SOURCEBeijing Science and Technology Project and Beijing Nova Program.