What is the peak time after intravenous administration for digoxin?

• A. 15 minutes
• B. 30 minutes
• C. 2 hours
• D. 6 hours

Answer: (B)

When a drug is given intravenously, there is no absorption phase to delay entry into the bloodstream. The time to peak concentration depends mainly on how long the infusion lasts and how quickly the drug distributes into tissues. Digoxin distributes fairly quickly, so its plasma level tends to reach a maximum near the end of a typical IV infusion. If the infusion is about 30 minutes, the peak plasma concentration is expected around 30 minutes. A shorter time (like 15 minutes) would be before the infusion ends, while longer times (such as 2 hours or 6 hours) are more characteristic of oral dosing or slower distribution, not the usual IV kinetics.