Which of the following reflects appropriate maximum IV potassium administration rates?

• A. Peripheral: 10 mEq/50 mL over 1 hour; Central: 20 mEq/100 mL over 1 hour
• B. Peripheral: 20 mEq/100 mL over 4 hours; Central: 40 mEq/200 mL over 2 hours
• C. Peripheral: 5 mEq/50 mL over 4 hours; Central: 15 mEq/100 mL over 2 hours
• D. Peripheral: 50 mEq/250 mL over 1 hour; Central: 60 mEq/300 mL over 2 hours

Answer: (A)

Potassium IV must be given slowly to avoid dangerous heart rhythms. The safe maximum rates are 10 mEq per hour through a peripheral IV and 20 mEq per hour through a central line. The option that shows 10 mEq in 50 mL over 1 hour for a peripheral line and 20 mEq in 100 mL over 1 hour for a central line matches these limits, so it represents the appropriate maximum. Other options either use slower rates that are below the maximum or exceed safe limits (for example, far too rapid peripheral administration or an excessively high central rate), which is why they aren’t appropriate.