Injectable Zinc Dosing for Deficiency
For acquired zinc deficiency requiring parenteral administration, give 0.5-1 mg/kg per day of elemental zinc IV for 3-4 months, which translates to approximately 35-70 mg daily for a 70 kg adult. 1, 2
Standard IV Dosing Framework
Weight-based dosing of 0.5-1 mg/kg per day elemental zinc is the cornerstone approach for treating acquired zinc deficiency when parenteral administration is necessary 1, 2
For a 50 kg adult: 25-50 mg elemental zinc daily 2
For a 60 kg adult: 30-60 mg elemental zinc daily 2
Treatment duration should be 3-4 months with monitoring of zinc levels 1, 2
Critical Administration Warnings
Direct intramuscular or intravenous injection of zinc chloride is absolutely contraindicated due to the acidic pH (pH 2) causing severe tissue irritation 3
Zinc must be diluted in parenteral nutrition solutions or appropriate IV fluids before administration 3
The solution contains no preservatives and must be used promptly in a single operation; discard unused portions immediately 3
Special Clinical Circumstances Requiring Higher Doses
Patients with ongoing gastrointestinal losses (fistulae, stomas, diarrhea) while nil per mouth: IV doses up to 12 mg per day are usually sufficient to maintain status for as long as losses persist 1
Major burns >20% body surface area: 30-35 mg/day IV for 2-3 weeks due to exudative losses 1
Acrodermatitis enteropathica: Requires lifelong oral intake of 3 mg/kg per day elemental zinc, adjusted to plasma levels 1
Mandatory Monitoring Requirements
Measure plasma zinc to confirm deficiency and monitor adequacy, with simultaneous CRP and albumin determination for proper interpretation 1
Check copper levels concurrently when initiating zinc supplementation, as zinc induces intestinal metallothionein that blocks copper absorption 1, 4
Recheck zinc and copper levels after 3 months of supplementation 1, 2
Maintain zinc-to-copper ratio of 8-15 mg zinc to 1 mg copper when providing both supplements 1, 4
Critical Safety Considerations
Severe kidney disease requires dose reduction or omission because zinc is primarily eliminated in urine 3
Aluminum toxicity warning: The product contains aluminum that may reach toxic levels with prolonged parenteral administration in impaired kidney function, particularly in premature neonates 3
Zinc supplementation without proportional copper replacement causes copper deficiency presenting as anemia, neutropenia, thrombocytopenia, and myeloneuropathy 4, 5
If copper levels fall during zinc supplementation, refer for specialist advice 1
Zinc Toxicity Thresholds
Symptoms of acute zinc toxicity (nausea, vomiting, epigastric pain, lethargy) appear when ingestion exceeds 1-2 grams 2
Chronic toxicity manifests at doses of 100-300 mg/day with induced copper deficiency, anemia, neutropenia, and impaired immune function 5
The tolerable upper intake level is 25 mg/day (EFSA) to 40 mg/day (FDA) for oral supplementation 6
Common Pitfalls to Avoid
Never administer zinc undiluted by direct injection into peripheral veins due to infusion phlebitis risk and increased excretory losses from bolus injection 3
Do not give zinc without monitoring copper, as administration in the absence of copper causes decreased serum copper levels 3
Bariatric surgery patients and those with inflammatory bowel disease require routine copper monitoring due to higher risk of zinc-induced copper deficiency 4