Efficacy of Thiamine (Vitamin B1) on Post-acute COVID-19 Syndrome: An Open-Label, Randomized, Controlled Trial

Background: Thiamine (vitamin B1) has the potential to influence the severity of various diseases by enhancing immune function. However, its role in the manifestations of coronavirus disease 2019 (COVID-19) remains inadequately understood. Objectives: This study aimed to investigate the efficacy of thiamine in alleviating symptoms of post-acute COVID-19 syndrome. Methods: In this open-label, randomized, controlled trial, 66 recovered COVID-19 patients experiencing post-acute COVID-19 syndrome were enrolled. Participants were randomly assigned to two groups: An intervention group receiving vitamin B1 alongside supportive therapy and a control group receiving supportive therapy alone. Symptom frequency and severity were monitored weekly over a nine-week period as study outcomes. Data were analyzed using SPSS. Results: The mean age of participants was 49.35 ± 13.83 years. Findings showed that vitamin B1 administration significantly shortened the duration for symptom improvement compared to the control group, with effects observed within two weeks (P < 0.0001). Unlike the control group, many symptoms—including myalgia, anosmia, ageusia, fatigue, and sleep disturbances—showed improvement after five weeks of vitamin B1 supplementation (P < 0.05). From the seventh week onwards, the recovery rate in the vitamin B1 group was twice that of the control group. Conclusions: Our findings indicate that vitamin B1 administration can significantly reduce the duration of post-acute COVID-19 syndrome. For post-acute COVID-19 patients, vitamin B1 supplementation along with appropriate supportive therapy is recommended to enhance recovery rates.