What is the most appropriate time to evaluate a peak digoxin level after oral administration?

What is the most appropriate time to evaluate a peak digoxin level after oral administration?

• A. 8 hours after a dose
• B. Immediately before the next dose
• C. Immediately after a dose
• D. 3 days after a dose

Answer: (A)

When evaluating a peak digoxin level, you’re aiming to capture the highest concentration in the blood after a dose. After oral administration, digoxin is absorbed slowly from the gut, so the maximum plasma level is reached several hours later. In clinical practice, this peak typically occurs about 6–8 hours after a dose, so sampling at around 8 hours post-dose best reflects the peak concentration and helps assess whether the dose is appropriate or carries a risk of toxicity. Sampling immediately before the next dose would measure the trough level, which informs ongoing exposure but not the peak. Sampling immediately after dosing or days later would not reflect the true peak.

When evaluating a peak digoxin level, you’re aiming to capture the highest concentration in the blood after a dose. After oral administration, digoxin is absorbed slowly from the gut, so the maximum plasma level is reached several hours later. In clinical practice, this peak typically occurs about 6–8 hours after a dose, so sampling at around 8 hours post-dose best reflects the peak concentration and helps assess whether the dose is appropriate or carries a risk of toxicity. Sampling immediately before the next dose would measure the trough level, which informs ongoing exposure but not the peak. Sampling immediately after dosing or days later would not reflect the true peak.