Zinc (Acetate, Sulfate, Gluconate)
Zinc acetate, Zinc sulfate, Zinc gluconate
Also known as: Galzin · Zinca-Pak · Various trade names · E650 · zinci acetas dihydricus · zinc sulphate · zinci sulfas · zincum sulfuricum · zinc methionine · Zinc sulfate · Zinc gluconate · Zinc acetate
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Audited v13 dosing evidence
Structured calculator evidencePrimary copper hepatopathy (extra-label)
- q12-24h
NA
Governing clinical context (1)
- NOTE: Zinc products may be labeled with concentrations expressed as salt OR as elemental zinc. Assume the labeled concentration per tablet or capsule is elemental zinc unless the labeled ingredients and concentrations state otherwise. Dosages below are for elemental zinc unless otherwise noted.
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Zinc is an essential trace element and nutritional agent critical for the function of over 200 metalloenzymes in the body. It plays a vital role in maintaining the structural integrity of cell membranes and nucleic acids, and is necessary for cell growth, immune response, wound healing, and vision.
In veterinary medicine, zinc is primarily utilized for:
- Zinc-Responsive Dermatoses:
- Syndrome I: A genetic defect in zinc absorption seen primarily in Northern breeds (e.g., Siberian Huskies, Alaskan Malamutes).
- Syndrome II: Occurs in rapidly growing large-breed puppies fed diets high in phytates or calcium, which bind dietary zinc and prevent its absorption.
- Hepatic Copper Toxicosis: Used in susceptible breeds (e.g., Bedlington Terriers, West Highland White Terriers, Labrador Retrievers) to block the intestinal absorption of copper.
- Hepatic Fibrosis & Lipidosis: Used as an adjunctive hepatoprotectant and antifibrotic agent.
Clinical Pearl: It is critical to distinguish between elemental zinc and zinc salts when calculating doses. For example, zinc sulfate contains 23% elemental zinc, while zinc gluconate contains only 14.3%. Always verify which form the dosage protocol is referencing.
Mechanism of action
Zinc acts as a critical cofactor for numerous metalloenzymes, including alkaline phosphatase, alcohol dehydrogenase, carbonic anhydrase, and RNA polymerase.
Mechanism in Copper Toxicosis: When administered orally in large doses, zinc induces the synthesis of metallothionein in intestinal enterocytes. Metallothionein is a cysteine-rich protein that has a much higher binding affinity for copper than for zinc. Dietary zinc → Induces enterocyte metallothionein → Binds dietary and biliary copper → Traps copper within the enterocyte → Enterocyte is sloughed into the feces (normal turnover) → Negative copper balance.
Safety & warnings
Contraindications
- Patients with pre-existing copper deficiency
- Patients with copper deficiency
Adverse effects
- Gastrointestinal disturbances (vomiting, nausea, anorexia)
- Hematologic abnormalities (hemolytic anemia, particularly at serum levels >1000 mcg/dL)
- Hypotension (with overdose)
- Jaundice (with overdose)
- Pulmonary edema (with overdose)
- Diarrhoea
- Haemolysis (at high doses)
Precautions
Zinc supplementation should be carefully considered before administering to patients with copper deficiency. When dosing, do not confuse the concentrations of zinc salts with elemental zinc. Zinc overdoses (e.g., ingestion of U.S. pennies minted after 1982) can be highly toxic and potentially fatal, causing severe hemolytic anemia.
Drug interactions
Large doses of zinc inhibit copper absorption in the intestine; separate supplements by at least 2 hours.
Zinc salts may reduce the oral absorption of fluoroquinolones.
May potentially inhibit zinc absorption; clinical significance is not clear.
Zinc salts may chelate oral tetracycline and reduce its absorption; separate doses by at least 2 hours.
May potentially inhibit zinc absorption; clinical significance is not clear.
Long-term administration of zinc may lead to decreased iron stores and functional deficiency
May potentially inhibit zinc absorption
Zinc salts may reduce the absorption of fluoroquinolone antibiotics
Monitoring
- Serum zinc levels (Target 200-500 mcg/dL for copper toxicosis; do not exceed 1000 mcg/dL)
- Gastrointestinal signs (vomiting, anorexia)
- Complete Blood Count (CBC) to monitor for hemolysis/anemia
- Clinical response (resolution of dermatosis or hepatic signs)
- Serum copper levels
- Complete Blood Count (CBC) / PCV to monitor for haemolysis
Pharmacokinetics
Half-life
Absorption
About 20-30% of dietary zinc is absorbed, principally from the duodenum and ileum. Bioavailability is dependent upon the food in which it is present. Phytates can chelate zinc and form insoluble complexes in an alkaline pH.
Distribution
Stored mostly in red and white blood cells, but is also found in the muscle, skin, bone, retina, pancreas, liver, kidney, and prostate.
Metabolism
Required by over 200 metalloenzymes for proper function.
Elimination
Primarily via the feces, but some is also excreted by the kidneys and in sweat. Zinc found in feces may be reabsorbed in the colon.
Overdose
Signs associated with overdoses of zinc in mammals include hemolytic anemia, hypotension, jaundice, vomiting, and pulmonary edema.
Toxicity Alert: Ingestion of U.S. pennies minted after 1982 is a common cause of severe zinc toxicosis in dogs, as these coins are 97.5% zinc.
Treatment in Mammals:
- Remove the source (e.g., endoscopic or surgical removal of coins).
- Dilution with milk or water.
- Chelation therapy using edetate calcium disodium (Calcium EDTA).
Avian Toxicity: Zinc intoxication in birds is relatively common (often from cage wire or hardware). Clinical signs are varied and nonspecific: lethargy, anorexia, regurgitation, polyuria, polydipsia, hematuria, hematochezia, pallor, dark or bright green diarrhea, foul-smelling feces, paresis, seizures, and sudden death. Treatment involves removing the source, chelation therapy (Calcium EDTA or succimer), and supportive care.
Available products
Formulations
- Capsules
- Tablets
- Injection
- Topical ophthalmic preparations
- Oral tablet
- Oral capsule
- Oral liquid
- Chelated preparations
Veterinary
- None as single-ingredient products for systemic use; several vitamin/mineral supplements contain zinc.
- Various zinc sulphate preparations
- Various zinc gluconate preparations
- Various zinc acetate preparations
- Chelated zinc preparations
Human-labeled
- Zinc Acetate Capsules: 25 mg & 50 mg (Galzin)
- Zinc Injection: 1 mg/mL & 5 mg/mL (Zinca-Pak)
- Zinc Gluconate Tablets: 10 mg, 15 mg & 50 mg
- Various zinc supplements (sulphate, gluconate, acetate)
Regulatory status
Available as POM, P, and general sale depending on formulation.
Available as POM, P, and general sale depending on formulation.
No regulatory data for: 🇺🇸 US · 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store zinc acetate crystals and zinc sulfate products in tight containers at room temperature unless otherwise recommended by the manufacturer.
Client information
Administering Zinc to Your Pet
- Empty Stomach is Best: Zinc is absorbed best when given on an empty stomach (1 hour before or 2 hours after meals).
- Managing Nausea: Zinc can be very irritating to the stomach. If your pet vomits after taking the medication, you can hide the capsule contents in a small amount of strong-smelling food, like a meatball of hamburger or a tablespoon of tuna fish (in oil).
- Do Not Mix with Certain Foods: Avoid giving zinc with dairy products or high-fiber foods, as these can prevent the zinc from being absorbed.
Important Safety Warnings
- Penny Toxicity: Keep loose change away from your pets! U.S. pennies minted after 1982 are made almost entirely of zinc. Swallowing even one or two pennies can cause severe, life-threatening anemia in dogs.
- Follow Instructions Carefully: There is a big difference between "elemental zinc" and "zinc salts" (like zinc sulfate). Always use the exact product and dose your veterinarian prescribed to avoid accidental overdose.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.