Medical Matters > Treatment: High-dose Vitamin C

ME Essential Summer 2020


I have read about the use of high dose vitamin C injections being used to treat people with coronavirus infection. Could this also be used to treat ME?


In our current state of knowledge I would not recommend the use of high-dose vitamin supplements, including Vitamin C, as a treatment for ME/CFS. Taking high doses of vitamin C can also cause a number of side effects:

  • Diarrhoea
  • Nausea
  • Vomiting
  • Heartburn
  • Abdominal cramps
  • Headache
  • Insomnia

There is no reliable evidence to indicate that people with ME/CFS have vitamin deficiencies (with the exception of vitamin D) and no evidence from clinical trials to indicate that vitamins are a safe and effective form of treatment. The situation regarding the use of intravenous Vitamin C as a possible treatment for Covid-19 remains very speculative and unproven.

More information


Information provided by The ME Association should not be construed as medical advice. Don't assume any new or worsened symptoms are simply the result of having ME/CFS or Long Covid. We recommend that any information you deem relevant is discussed with your NHS GP as soon as possible. It is important that you seek personalised medical advice from the GP who is in charge of your care and who knows you well.

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