Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling.
Capsule, Oral:
Galzin: 25 mg, 50 mg
Pharmacology
Mechanism of Action
Zinc induces production of the copper binding protein metallothionein in enterocytes. Copper binding within enterocytes results in an impairment of the intestinal absorption of dietary copper and reabsorption of endogenously secreted copper in saliva, bile, gastric acid. Following enterocyte desquamation, bound copper is eliminated in the feces.
Pharmacokinetics/Pharmacodynamics
Absorption
Small intestine (IOM 2001); impaired with food and beverages (other than water)
Distribution
Stored primarily in skeletal muscle and bone (IOM 2001)
Excretion
Feces and urine (IOM 2001)
Protein Binding
Primarily to albumin (IOM 2001)
Use: Labeled Indications
Wilson disease: Maintenance treatment of Wilson disease following chelation therapy.
Contraindications
Hypersensitivity to zinc acetate or any component of the formulation.
Dosage and Administration
Dosing: Adult
Wilson disease: Oral: Note: Dose expressed in mg elemental zinc:
Usual dosage: 50 mg 3 times daily; may administer 25 mg 3 times daily if patient is compliant with therapy (increase dose to 50 mg 3 times daily if inadequate response to lower dose).
Pregnant females: 25 mg 3 times daily; may increase to 50 mg 3 times daily if inadequate response to lower dose.
Dosing: Geriatric
Refer to adult dosing.
Dosing: Pediatric
Wilson disease: Note: Dose expressed in mg of elemental zinc:
Children ≥5 years to <10 years: Limited data available: Oral: 25 mg 3 times daily (AASLD [Roberts 2008])
Children ≥10 years and Adolescents: Oral: 25 to 50 mg 3 times daily (AASLD [Roberts 2008]; manufacturer's labeling)
Administration
Oral: Administer on empty stomach at least 1 hour before or 2 to 3 hours after meals, and at least 1 hour separated from beverages other than water. Gastric irritation is most commonly associated with morning dose; may administer morning dose between breakfast and lunch if gastric irritation occurs. Swallow capsule whole; do not chew or open.
Storage
Store at 25°C (77°F); excursions permitted to 15°C to 30°C (59°F to 86°F). Protect from light.
Drug Interactions
Baloxavir Marboxil: Polyvalent Cation Containing Products may decrease the serum concentration of Baloxavir Marboxil. Avoid combination
Bictegravir: Polyvalent Cation Containing Products may decrease the serum concentration of Bictegravir. Management: Administer bictegravir under fasting conditions at least 2 hours before or 6 hours after polyvalent cation containing products. Coadministration of bictegravir with or 2 hours after most polyvalent cation products is not recommended. Consider therapy modification
Bisphosphonate Derivatives: Polyvalent Cation Containing Products may decrease the serum concentration of Bisphosphonate Derivatives. Management: Avoid administration of oral medications containing polyvalent cations within: 2 hours before or after tiludronate/clodronate/etidronate; 60 minutes after oral ibandronate; or 30 minutes after alendronate/risedronate. Exceptions: Pamidronate; Zoledronic Acid. Consider therapy modification
Ceftibuten: Zinc Salts may decrease the serum concentration of Ceftibuten. Management: Consider administering oral zinc salts at least 3 hours after ceftibuten. Consider therapy modification
Cephalexin: Zinc Salts may decrease the absorption of Cephalexin. Management: Consider administering oral zinc salts at least 3 hours after cephalexin. Consider therapy modification
Deferiprone: Polyvalent Cation Containing Products may decrease the serum concentration of Deferiprone. Management: Separate administration of deferiprone and oral medications or supplements that contain polyvalent cations by at least 4 hours. Consider therapy modification
Dolutegravir: Zinc Salts may decrease the serum concentration of Dolutegravir. Management: Administer dolutegravir at least 2 hours before or 6 hours after oral zinc salts. Administer the dolutegravir/rilpivirine combination product at least 4 hours before or 6 hours after oral zinc salts. Consider therapy modification
Eltrombopag: Polyvalent Cation Containing Products may decrease the serum concentration of Eltrombopag. Management: Administer eltrombopag at least 2 hours before or 4 hours after oral administration of any polyvalent cation containing product. Consider therapy modification
PenicillAMINE: Polyvalent Cation Containing Products may decrease the serum concentration of PenicillAMINE. Management: Separate the administration of penicillamine and oral polyvalent cation containing products by at least 1 hour. Consider therapy modification
Quinolones: Zinc Salts may decrease the serum concentration of Quinolones. Management: Give oral quinolones at least several hours before (4 h for moxi- and sparfloxacin, 2 h for others) or after (8 h for moxi-, 6 h for cipro/dela-, 4 h for lome-, 3 h for gemi-, and 2 h for levo-, nor-, pe- or ofloxacin or nalidixic acid) oral zinc salts. Exceptions: LevoFLOXacin (Oral Inhalation). Consider therapy modification
Raltegravir: Polyvalent Cation Containing Products may decrease the serum concentration of Raltegravir. Management: Administer raltegravir 2 hours before or 6 hours after administration of the polyvalent cations. Dose separation may not adequately minimize the significance of this interaction. Consider therapy modification
Tetracyclines: Zinc Salts may decrease the absorption of Tetracyclines. Only a concern when both products are administered orally. Management: Consider doxycycline as a noninteracting tetracycline derivative. Separate dose administration of oral tetracycline derivative and oral zinc salts by at least 2 hours to minimize interaction. Exceptions: Doxycycline; Eravacycline. Consider therapy modification
Trientine: Polyvalent Cation Containing Products may decrease the serum concentration of Trientine. Management: Avoid concomitant administration of trientine and oral products that contain polyvalent cations. If oral iron supplements are required, separate the administration by 2 hours. If other oral polyvalent cations are needed, separate administration by 1 hour. Consider therapy modification
Adverse Reactions
Frequency not defined.
Central nervous system: Neurological deterioration (uncommon)
Gastrointestinal: Gastric irritation, increased serum amylase, increased serum lipase
Hepatic: Increased serum alkaline phosphatase
<1%, postmarketing, and/or case reports: Hepatic insufficiency
Warnings/Precautions
Concerns related to adverse effects:
- Central nervous system: Neurological deterioration may occur with initial therapy as copper stores are mobilized; effects are less common when compared to chelation therapy.
- GI effects: Gastric irritation/upset may occur with use and particularly with the morning dose.
Other warnings/precautions:
- Appropriate use: Not recommended for initial treatment of Wilson disease in symptomatic patients; may be used as maintenance therapy after patient has been stabilized on initial chelation therapy.
- Therapy management: Hepatic copper levels should not be used to manage therapy as they do not differentiate between potentially toxic free copper and safely bound copper.
Monitoring Parameters
Serum non-ceruloplasmin bound copper, 24-hour urinary copper excretion, 24-hour urinary zinc level; LFTs, neurologic evaluation including speech
Pregnancy
Pregnancy Risk Factor
A
Pregnancy Considerations
Adequate, well-controlled studies in pregnant women have not shown an increased risk of fetal abnormalities. The risk of fetal harm appears remote with use of zinc acetate during pregnancy.
Patient Education
- Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)
- Patient may experience nausea, vomiting, or diarrhea. Have patient report immediately to prescriber signs of pancreatitis (severe abdominal pain, severe back pain, severe nausea, or vomiting) (HCAHPS).
- Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.
Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for health care professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience, and judgment in diagnosing, treating, and advising patients.
