ZINC SULFATE
Clinical safety rating: caution
Comprehensive clinical and safety monograph for ZINC SULFATE (ZINC SULFATE).
Zinc sulfate provides essential zinc, a cofactor for over 300 enzymes involved in cell division, DNA synthesis, immune function, and wound healing. It stabilizes cell membranes and has antioxidant properties.
| Metabolism | Zinc is not metabolized; it is absorbed in the small intestine, distributed bound to albumin and alpha-2-macroglobulin, and excreted primarily in feces via pancreatic and biliary secretions. Renal excretion is minimal. |
| Excretion | Zinc is primarily excreted in feces (approximately 90%) via biliary and pancreatic secretions, with renal excretion accounting for about 2-10% of total elimination. Minor amounts are lost in sweat and sloughed intestinal cells. |
| Half-life | The terminal elimination half-life of zinc sulfate is approximately 2.5-3 hours in normal subjects; however, the whole-body turnover half-life is considerably longer (12-14 days), reflecting redistribution from exchangeable pools. |
| Protein binding | Approximately 60-70% of circulating zinc is bound to albumin; about 30-40% is bound to alpha-2-macroglobulin; a small fraction (<5%) is bound to transferrin and other proteins. |
| Volume of Distribution | The apparent volume of distribution (Vd) for zinc is estimated to be about 1.2-1.5 L/kg, indicating extensive distribution into total body water and tissue binding. |
| Bioavailability | Oral bioavailability of zinc sulfate is approximately 20-30% under fasting conditions, but can vary widely (15-60%) depending on food intake (decreased by phytates, increased by animal proteins). |
| Onset of Action | Oral: Clinical improvement in zinc deficiency symptoms (e.g., dermatitis, impaired wound healing) typically begins within 1-2 weeks of adequate replacement therapy. Intravenous: Onset is immediate upon administration for parenteral nutrition support. |
| Duration of Action | The duration of action depends on the zinc status and dose. For replacement therapy, effects persist as long as adequate zinc levels are maintained; after cessation, tissue stores may be depleted over weeks to months. |
| Molecular Weight | 287.56 |
For zinc deficiency: 220 mg (containing 50 mg elemental zinc) orally three times daily. For maintenance: 110 mg (25 mg elemental zinc) orally once daily.
| Dosage form | SOLUTION |
| Renal impairment | No specific GFR-based dose adjustment recommended; monitor serum zinc levels in severe renal impairment (CrCl <30 mL/min) due to risk of accumulation. |
| Liver impairment | No adjustment required for Child-Pugh Class A or B. Use with caution in Class C due to decreased albumin binding; monitor zinc levels. |
| Pediatric use | For deficiency: 2-3 mg/kg/day of elemental zinc orally in 2-3 divided doses, not to exceed 75 mg/day elemental zinc. For maintenance: 1-2 mg/kg/day elemental zinc. |
| Geriatric use | Start at lower end of dosing range; monitor renal function and serum zinc levels due to age-related decline in renal function. |
| 1st trimester | Zinc sulfate is generally considered safe in recommended doses during the first trimester. It is an essential trace mineral; however, excessive intake may be harmful. The RDA for pregnancy is 11 mg/day; doses above 40 mg/day may cause toxicity. |
| 2nd trimester | Same as t1; maintain recommended dietary allowance. Zinc deficiency during pregnancy may lead to fetal growth restriction, but supplementation should be within RDA limits. |
| 3rd trimester | Same as t2; continue recommended supplementation if needed. High doses may interfere with copper absorption and cause maternal toxicity. |
Clinical note
Comprehensive clinical and safety monograph for ZINC SULFATE (ZINC SULFATE).
| Placental transfer | Zinc actively crosses the placenta via transporters; maternal-fetal transfer is regulated. Adequate zinc is essential for fetal growth; deficiency can impair development. |
| Breastfeeding | Zinc is excreted into breast milk in small amounts and is essential for infant development. Supplements within the RDA (12 mg/day for lactating women) are safe. High doses (above RDA) should be avoided unless prescribed for deficiency. |
■ FDA Black Box Warning
None.
| Serious Effects |
Hypersensitivity to zinc sulfateWilson's disease (relative, may increase copper deficiency)
| Precautions | Copper deficiency with prolonged use (monitor copper levels), Gastric irritation (take with food), Kidney impairment (dose adjustment may be needed), Drug interactions: reduce absorption of tetracyclines, quinolones, penicillamine, and iron |
| Food/Dietary | Take with food to reduce GI upset. Avoid concurrent ingestion of high-phytate foods (bran, whole grains, legumes), high-fiber foods, and dairy products, as they reduce zinc absorption. Caffeine and alcohol may also impair zinc absorption. Separate intake of iron or calcium supplements by at least 2 hours. |
Loading safety data…
| Lactation Rating | L1 (Safe, compatible with breastfeeding when used in recommended doses) |
| Teratogenic Risk | Zinc sulfate is essential for normal fetal development. At recommended dietary allowance doses, no teratogenic risk has been identified. High doses (supplementation above tolerable upper intake level) may cause maternal copper deficiency and potential fetal effects, but specific teratogenic risks are not established. First trimester: no known teratogenicity at physiological doses. Second and third trimesters: no known adverse fetal effects at physiological doses. |
| Fetal Monitoring | No specific fetal monitoring is required for zinc sulfate at physiological doses. For high-dose supplementation, monitor maternal serum zinc and copper levels to avoid copper deficiency; monitor for signs of maternal toxicity. |
| Fertility Effects | Zinc is essential for reproductive health. Deficiency can impair fertility; adequate levels support normal spermatogenesis and ovulation. No adverse effects on fertility at physiological doses. High doses may disrupt copper balance and indirectly affect fertility. |
| Clinical Pearls |
| Zinc sulfate is often used for patients with zinc deficiency, which can manifest as dermatitis, poor wound healing, or immune dysfunction. Administer with food to reduce gastrointestinal irritation, but avoid high-fiber or phytate-rich foods (e.g., whole grains, legumes) that chelate zinc and reduce absorption. Monitor for copper deficiency with long-term use, as zinc inhibits copper absorption. Intravenous zinc can cause hypotension and bradycardia if infused too rapidly. |
| Patient Advice | Take this medication with food to prevent stomach upset, but avoid high-fiber foods or whole grains at the same time. · Do not take zinc supplements with dairy products, as calcium may reduce absorption. · Inform your doctor if you experience nausea, vomiting, or metallic taste. · Do not exceed the recommended dose, as high zinc levels can be toxic. · Keep out of reach of children; accidental overdose can be serious. |