In parenteral nutrition, adverse effects from zinc have been observed at what minimum daily dose?

• A. 30 mg or greater
• B. 20 mg or greater
• C. 40 mg or greater
• D. 50 mg

Answer: (A)

High-dose zinc in parenteral nutrition can reach toxicity, primarily by disrupting copper metabolism and impacting hematologic and immune function. Adverse effects have been observed when daily zinc intake is about 30 mg or more, making this a practical threshold clinicians watch for when monitoring PN patients. Lower intakes reduce the risk of toxicity, though individual tolerance and duration of therapy matter. So the minimum daily dose at which adverse effects have been reported is around 30 mg per day.