Zinc Sulfate Injection

Zinc Sulfate Injection is a sterile, preservative-free aqueous solution intended exclusively for intravenous use as a trace-element additive in parenteral nutrition formulations; each milliliter delivers ionized zinc that the body cannot synthesize and that is required to support hundreds of metallo-enzymes, nucleic-acid stability, and normal immune competence.

The product described here is compounded in a 503B outsourcing facility and supplied in two labeled concentrations: a 30 mL vial containing 10 mg zinc/mL for pharmacy bulk preparation and a 10 mL single-dose vial containing 1 mg zinc/mL that corresponds to a commercially manufactured presentation.

According to current labeling, the solution is clear, colorless to pale straw, with a pH adjusted by sulfuric acid; it is designated Rx-only and must be diluted into a balanced amino acid/glucose admixture before infusion to avoid venous irritation or renal zinc wasting.

The clinical rationale for parenteral zinc supplementation was established after total parenteral nutrition (TPN) became widespread; observational data showed that omission of zinc led to growth failure, hypogonadism, and the fatal acrodermatitis enteropathica phenotype in long-term recipients.

Large reviews of trace-element physiology further demonstrate that zinc deficiency, even when subclinical, impairs wound healing, alters taste and smell, and predisposes to infectious complications, situating intravenous zinc as a core component of evidence-based nutrition support strategies.

Zinc serves as a catalytic or structural co-factor for over 300 enzymes, including DNA and RNA polymerases, alkaline phosphatase, and superoxide dismutase; by binding to cysteine and histidine residues it stabilizes tertiary protein structure and modulates gene expression via zinc-finger motifs,.

Within the bloodstream, most infused zinc binds rapidly to albumin and α-2-macroglobulin; cellular uptake is then mediated by ZIP (Zrt/Irt-like Protein) importers and ZnT exporters whose coordinated activity maintains nanomolar cytosolic concentrations while permitting millimolar sequestration in secretory vesicles-regulation that is crucial during stresses such as burns or sepsis when requirements rise markedly,.

Once internalized, zinc acts as an anti-oxidant surrogate by inducing metallothionein, a cysteine-rich peptide that scavenges free radicals and buffers transition-metal toxicity; experimental models show that zinc depletion heightens oxidative DNA damage and increases permeability of epithelial barriers.

Conversely, excessive intracellular zinc can initiate apoptosis through mitochondrial dysfunction and antagonize copper-dependent enzymes, underscoring the importance of precise dosing in parenteral formulations.

Administration is contraindicated in patients with known hypersensitivity to zinc salts or any component of the formulation and in those with severe brittle anemia where additional zinc could impede copper utilization, as noted in labeling.

Because the bulk-vial presentation contains detectable aluminum, prolonged use in premature neonates or individuals with impaired renal clearance warrants extreme caution to avoid cumulative neurotoxic exposure.

Clinicians must also consider pre-existing low serum copper: repeated high-dose zinc infusions accelerate enteral metallothionein expression, sequestering dietary copper and precipitating secondary hypocupremia that manifests as anemia and neutropenia.

Zinc competes with copper and iron for shared divalent-metal transporter-1 (DMT-1) pathways; pharmacodynamic antagonism is clinically relevant when high-dose zinc is combined with intravenous iron dextran or oral copper supplements, potentially producing reciprocal deficiencies.

Compatibility data compiled by parenteral-nutrition societies indicate that zinc chelates with calcium and phosphate at concentrations exceeding customary PN ranges; meticulous order of mixing and maintenance of acidic pH (<6.0) prevent precipitation.

Chelating agents such as penicillamine or ethylenediaminetetraacetic acid (EDTA) can markedly increase renal excretion of zinc, whereas corticosteroids may induce a negative zinc balance by promoting urinary losses, necessitating monitoring in long-term PN.

Local infusion-site phlebitis can occur if the concentrate is administered undiluted or infused through peripheral veins; pain, erythema, and sclerosis have been described when concentrations exceed 1 mg zinc/mL.

Systemic adverse reactions are uncommon at recommended doses but may include diaphoresis, dizziness, nausea, and, in extreme overdoses, hypotension and pulmonary edema attributable to direct endothelial injury.

Labeling reports that fetal safety data are limited; therefore inadvertent maternal exposure beyond physiological requirements could, in theory, disturb embryonic copper metabolism, although controlled studies in humans are lacking.

Prolonged parenteral supplementation without laboratory surveillance has occasionally led to hypozincemia (>200 µg/dL) with concomitant hypocupremia; cases resolved after dose reduction and copper repletion, emphasizing the need for monthly trace-element panels in stable home-PN patients.

Pregnancy category C applies to intravenous zinc: animal studies are inadequate, and well-controlled human investigations are absent; nevertheless, parenteral doses within the Dietary Reference Intake (11-12 mg elemental zinc/day) are not expected to pose teratogenic risk, whereas severe maternal deficiency correlates with pre-term birth.

When parenteral nutrition is indispensable during hyperemesis gravidarum or severe malabsorption, clinicians may cautiously titrate zinc sulfate to maintain serum levels between 70 and 120 µg/dL, balancing the essential role of zinc in neural-tube development against theoretical concerns of copper-zinc antagonism.

Vials should be stored at controlled room temperature, 20 – 25 °C (68 – 77 °F); exposure to extreme heat may accelerate pH drift and precipitate insoluble zinc salts.

After first puncture of a pharmacy bulk vial, the contents must be used in a certified cleanroom within 4 hours, then discarded; single-dose vials offer reduced contamination risk but cannot be admixed directly into solutions containing bicarbonate.