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High-dose intravenous vitamin C is unlikely to improve COVID-19 outcomes


Vitamin C is a potent antioxidant with anti-inflammatory and immunosupportive properties. Previous clinical research has reported that intravenous administration of vitamin C had positive effects on patients with respiratory infection, lung injury, and sepsis. Given the above, it’s possible that high-dose intravenous vitamin C (HDIVC) administration could improve clinical outcomes in patients with COVID-19.

The study

In this five-day open-label randomized controlled trial in Tehran, Iran, 60 hospitalized COVID-19 patients (average age of 59 years) with oxygen saturation of less than 93% received either 1.5 grams of intravenous vitamin C every 6 hours in addition to standard treatment, which, at the time, was lopinavir/ritonavir and hydroxychloroquine, or only standard treatment.

The primary outcomes were mortality rate, duration of hospitalization, and need for ICU admission. The secondary outcomes were peripheral capillary oxygen saturations, vital signs, and the general well being of the patients.

The results

The median length of hospitalization in the HDIVC group was longer than the control group: 8.5 days vs. 6.5 days. There were no other differences between groups in the primary outcomes.

Compared to the control group, body temperature was lower in the HDIVC group on the third day of hospitalization, but not at discharge. However, body temperature was also lower in the HDIVC group at baseline. Moreover, compared to the control group, peripheral capillary oxygen saturations levels were higher (i.e., better) on the third day of hospitalization in the HDIVC group, but not at discharge.


Overall, the outcomes with HDIVC were not different than without HDIVC.

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