High Dose Vitamin C Therapy for Fever of Unknown Origin: A Case Report


There has been a growing evidence over the last few years of high dose vitamin C as a treatment for several medical conditions including but not limited to cancer, respiratory and systemic infections. (Gonzalez MJ, et al., 2014) prevention of infection requires dietary vitamin C intakes that provide at least proper plasma levels, which maintain cell and tissue levels. In contrast, treatment of established infections requires significantly higher doses of the vitamin to compensate for the increased inflammatory response and metabolic demand.(McGregor GP & Biesalski HK, 2006) Here we report a case of successful use of high-dose vitamin C in the treatment of presumed infection presenting as fever of unknown origin (FUO).



A 3-year-old girl was brought to the emergency department due to a history of high-grade fever for 8 days with an oral/axillary temperature of –. She sought medical advice several times where she received different oral antibiotics with no improvement. She has no history of any other symptoms and looks well and active between the spikes of fever. Her brother had fever at the same time, he was diagnosed as pharyngitis which subsided on an oral antibiotic and antipyretics. Otherwise, no relevant history or family history. Upon admission, she was vitally stable, clinical examination showed no focus of infection. All imaging studies came back within normal as chest x ray and abdominal ultrasound were unremarkable, while echocardiography revealed no vegetations. Blood tests showed white blood cells 12,000 cells/mm3 (neutrophils 8,460 and lymphocytes 2,860), C-reactive protein 8 mg/l, erythrocyte sedimentation rate 42 mm, procalcitonin 0.1 ng/ml. Furthermore, cytomegalovirus serology, monospot test, widal, brucella antibodies, influenza and respiratory syncytial virus swabs, rotavirus and adenovirus in stool were all negative. Moreover, liver function tests, kidney function tests, blood film, rheumatoid factor, antinuclear antibodies, complement 3 and 4 were all within normal. Therefore, apart from the erythrocyte sedimentation rate of 42 mm, all blood tests were normal. Urine analysis initially revealed white blood cells 8-10 per high power field, leucocytes (+) and few bacteria, while nitrite was negative. However, urine and blood cultures revealed no growth. The fever continued for a total duration of 18 days, despite a 5-day-course of intravenous ceftriaxone; therefore, the antibiotic was stopped and high-dose vitamin C was started at a dose of 5 grams oral per day divided into 5 doses; eventually, the fever has subsided gradually over the following 2 days. Furthermore, follow up after one week revealed no more fever or illness; now with follow-up of — weeks, the patient remains afebrile, with the only response-producing intervention being that of orally administered ascorbic acid.



Close correlation has been found between oxidative stress and viral infectious diseases. The elevated oxidants induced by viral infection contribute to viral pathogenesis, the modulation of cellular responses, and the regulation of viral replication and the host defense (Kim Y, et al. 2013). Vitamin C is an essential factor in the production of the anti-viral immune response during the early phase of viral infection through the production of type I interferons, which up-regulates NK cell and cytotoxic T-lymphocyte activity. (Doll S, & Ricou B, 2013) Vitamin C can be used as an inactivating agent for both RNA and DNA viruses, affecting viral infectivity. Furthermore, vitamin C can detoxify viral products that produce pain and inflammation.5 In summary, herein we have reported the case of 3-year-old girl with an 18-day history of FUO unresponsive to 5 days of intravenous antibiotic treatment which responded within 2 days to 5 grams daily of vitamin C.


Competing Interests

The authors declare that they have no competing interests.



Doll S & Ricou B (2013) Severe vitamin C deficiency in a critically ill adult: a case report. European journal of clinical nutrition, 67(8), 881.

Gonzalez MJ, Miranda-Massari JR, Berdiel MJ, Duconge J, Rodríguez-López JL, Hunninghake R & Cobas-Rosario VJ (2014) High dose intraveneous vitamin C and chikungunya fever: a case report. Journal of orthomolecular medicine: official journal of the Academy of Orthomolecular Medicine, 29(4), 154.

Kim Y, Kim H, Bae S, Choi J, Lim SY, Lee N, … Lee WJ (2013) Vitamin C is an essential factor on the anti-viral immune responses through the production of interferon-α/β at the initial stage of influenza A virus (H3N2) infection. Immune network, 13(2), 70-74.

McGregor GP & Biesalski HK (2006) Rationale and impact of vitamin C in clinical nutrition. Current Opinion in Clinical Nutrition & Metabolic Care, 9(6), 697-703.