Skip to 0 minutes and 11 secondsLet's start example number 3 for digoxin. Here we have MJ a 50 year old, 70 kilo, 5 foot and 10 inches male with atrial fibrillation. His doctor prescribed digoxin. In addition, he showed moderate, stabilized renal impairment, serum creatinine was 1.4. And the desired therapeutic concentration for this patient is 1.3 ng per ml. Now in order to solve this problem. You need to Oh The question is to calculate the IV digoxin loading dose to provide the therapeutic concentration as soon as possible. And I have a hint here for you. You need volume distribution in order to perform a calculation. And the second question is to calculate an oral maintenance dose to maintain the therapeutic concentration.

Skip to 1 minute and 25 secondsSo digoxin loading is equal to volume distribution times the therapeutic concentration which we already know. So first calculate ideal body weight based on the formula that we can find. Calculate body surface area using Dubois formula. Or there are some other formula that you can use but they all come up with about the same value. And it determined creatinine clearance by a cock-croft equation which turn out to be 62.5 ml per minutes. Now with the ideal body weight. And the body surface area and a creatinine clearance. You can estimate volume distribution by Jusko equation. And that is the Jusko equation. And the value turned out to be 464 liter. Therefore, when loading dose is equal to 603.2 microgram.

Skip to 2 minutes and 39 secondsSo how to give them? Give the 600 microgram Digoxin as a slow push 50 percent and then 25% every six hours. Now digoxin is given as a slow push in order to avoid hypotensive reaction.

Calculate IV Loading Dose of Digoxin : Example 3

In this step, Prof. Lee illustrates how to estimate the IV digoxin loading dose.

We know that we need the volume of distribution (V) by his hint.

Therefore, we should calculate the IBW and BSA first, then get Clcr by C-G equation to know V.

Finally, the product of V and the desired therapeutic concentration is the IV loading dose. We should notice that digoxin needs to be administered as a slow IV push.

Please try the exercise on your own to check your understanding, and share your answer below.

MT is a 60 yo, 80 kg, 5’10” male with atrial fibrillation, for which his doctor prescribed digoxin. In addition, he showed moderate, stabilized renal impairment, serum creatinine 1.4 mg/dl. The desired therapeutic concentration for this patient is 1.3 ng/ml. • Calculate an IV digoxin loading dose to provide the therapeutic concentration.

In the next step, we will discuss how to calculate the oral maintenance dose to maintain the therapeutic concentration of digoxin.

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This video is from the free online course:

Pharmacokinetics: Drug Dosing in Renal Disease

Taipei Medical University