Digoxin therapeutic level

0.8 to 2 ng/mL, and the potassium trap.

Short answer

The therapeutic digoxin level is 0.8 to 2 ng/mL. A level above 2 ng/mL is toxic. Just as important, a low potassium (under 3.5) can cause toxicity even when the digoxin level itself reads normal, so the potassium is checked alongside it.

What the digoxin level tells you, and why the NCLEX tests it

Digoxin has a narrow safety margin, so the exam constantly hands you a level and a potassium and asks whether it is safe to give the dose. Knowing the numbers and the potassium connection answers the question.

Key nursing considerations for the digoxin level

Therapeutic range

0.8 to 2 ng/mL.

Toxic threshold

Above 2 ng/mL is toxic.

The potassium link

Low potassium (under 3.5) worsens toxicity even at a normal level, and diuretics that lower potassium are often given with digoxin.

Toxicity signs

Anorexia, nausea, vomiting, yellow-green visual halos, confusion, and bradycardia.

Nursing response

Take an apical pulse for a full minute, hold for under 60 or signs of toxicity, notify, and anticipate digoxin immune Fab.

How the NCLEX turns the digoxin level into a question

The exam reuses a few predictable angles. Learn to spot them and the question answers itself.

Priority check the apical pulse and the potassium along with the level; hold and notify for a level above 2, a pulse under 60, or toxicity signs.

Lab digoxin 0.8 to 2 ng/mL and potassium 3.5 to 5.0.

Teach keep your lab appointments to check the level and potassium, and report nausea, loss of appetite, or seeing yellow halos.

NGN cue

A digoxin level of 1.6 ng/mL with a potassium of 3.1. Recognize that the low potassium can still cause toxicity; hold and notify even though the level looks normal.

Quick answers

What is a therapeutic digoxin level?

0.8 to 2 ng/mL. A level above 2 ng/mL is toxic.

Can digoxin be toxic at a normal level?

Yes. A low potassium (under 3.5) can cause toxicity even when the digoxin level is within range, which is why potassium is checked alongside the level.

What do you do for a high digoxin level?

Hold the dose, take an apical pulse for a full minute, notify the provider, and anticipate digoxin immune Fab (DigiFab) for serious toxicity.

Keep studying

These pages build on each other. Work through the related classes, then pressure-test yourself against the free cheat sheet and the full guide.


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