Are intramuscular injections of vitamin C (Vit C) (500mg) and glutathione (600mg) from Vitastir (Vitastir) effective and safe for general wellbeing?

Intramuscular Vitamin C and Glutathione for General Wellbeing

Intramuscular injections of vitamin C (500mg) and glutathione (600mg) are not recommended for general wellbeing in healthy individuals, as there is no evidence supporting their efficacy for this indication and they offer no advantage over oral supplementation when no deficiency or specific medical condition exists.

Evidence-Based Rationale

Vitamin C Supplementation Guidelines

The ESPEN micronutrient guideline establishes clear dosing recommendations that do not support routine intramuscular administration for general wellbeing 1:

• Healthy individuals require only 50-100 mg/day of vitamin C 1
• Standard parenteral nutrition provides 100-200 mg/day 1
• Higher doses (2-3 g/day IV) are reserved exclusively for critical illness during acute inflammation 1

The guideline explicitly states that plasma vitamin C measurement is not recommended in the absence of clinical suspicion of scurvy or chronic low intake 1. Your proposed 500mg intramuscular dose exceeds standard recommendations without medical justification.

Cancer and Micronutrient Guidelines

The ESPEN practical guideline on clinical nutrition in cancer strongly discourages high-dose micronutrients in the absence of specific deficiencies 1:

• Vitamins and minerals should be supplied in amounts approximately equal to the recommended daily allowance 1
• High-dose micronutrient supplementation is discouraged without documented deficiencies 1
• Multiple large randomized controlled trials showed that combined vitamin E (400 IU/day) and vitamin C (500 mg/day) supplementation for 10 years had no effect on cancer incidence in 14,641 physicians 1

Glutathione Evidence

The most recent high-quality evidence directly addresses your question. A 2025 double-blind, placebo-controlled crossover study in children tested weekly intravenous glutathione injections (600mg dose range) and found 2:

• No differences in behavioral or biologic measures between glutathione treatment and placebo 2
• No improvements when glutathione was combined with vitamin C 2
• Small improvements observed were attributed to placebo effect 2

A 2023 study in athletes testing combined vitamin C and glutathione supplementation showed metabolic effects only during prolonged submaximal exercise in trained triathletes—a specific performance context, not general wellbeing 3.

Safety Considerations for Intramuscular Injections

The pediatric guideline on rodent cancer models notes that intramuscular injections of vitamin A were painful 1, and this applies broadly to intramuscular vitamin injections. Research on intramuscular injection techniques emphasizes that while the procedure is common, it is not benign and unsafe injection practices have significant impacts on patient morbidity and mortality 4.

Common pitfalls to avoid:

• Intramuscular injections carry risks of pain, tissue damage, and infection that are not justified without clear medical indication 4, 5
• The 500mg vitamin C dose exceeds what is needed for general health and provides no additional benefit 1
• Glutathione injections lack evidence for efficacy in healthy individuals 2

Clinical Bottom Line

For general wellbeing in individuals without documented deficiencies or specific medical conditions:

• Oral multivitamin supplementation providing recommended daily allowances is appropriate 1
• Vitamin C needs are met with 50-100 mg/day orally 1
• Intramuscular administration adds unnecessary pain, cost, and risk without proven benefit 1, 4
• Glutathione supplementation, whether oral or parenteral, lacks evidence for improving wellbeing in healthy individuals 2

The only justified uses for higher-dose parenteral vitamin C are:

• Critical illness with acute inflammation (2-3 g/day IV) 1
• Documented vitamin C deficiency with clinical scurvy 1
• Chronic oxidative stress conditions like severe COPD or chronic dialysis (200-500 mg/day) 1