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Digoxin Immunoassay, Serum (Mass Concentration)

Published: August 9, 2026Updated: August 17, 2026

This test measures the amount of digoxin, a medication used to treat certain heart conditions, in your blood.

Quick summary

["Digoxin levels help ensure your medication dose is safe and effective."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
29216-9
Short code
Digoxin Fld-mCnc
Synonyms
Digoxin Fld-mCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Ref low
0.5
Ref high
2
Critical range
— – 4 N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why Is This Test Done?

Your healthcare provider may order this test if you’re taking digoxin to manage heart rhythm issues, heart failure, or other cardiac conditions. They may also check levels if you’re experiencing symptoms like irregular heartbeat, nausea, or fatigue, or if you’re adjusting your dose.

What Does the Test Involve?

A blood sample is taken from a vein, usually in your arm. The sample is sent to a lab where it’s analyzed to measure the exact amount of digoxin present.

What Do Results Mean?

Results are used to guide treatment decisions. Too much digoxin can cause side effects, while too little may mean your heart isn’t responding well to the medication. Your provider will interpret results in the context of your symptoms and medical history.

Common Reasons for Testing

This test is often done regularly if you’re on long-term digoxin therapy to monitor for toxicity or ensure proper dosing. It may also be checked after a dose adjustment or if you experience unusual symptoms.

Reference range

Therapeutic: 0.5-2.0 ng/mLN/A

Specimen: serum

No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Digoxin Level

Frequently asked questions

How often will I need this test?
The frequency depends on your treatment plan. Some patients need testing weekly or monthly, while others may only need it occasionally. Your healthcare provider will set a schedule based on your specific needs and how your body responds to the medication.
What happens if my digoxin level is too high?
If your level is too high, it may cause symptoms like vomiting, dizziness, or a fast or irregular heartbeat. Your provider will adjust your dose or temporarily stop the medication to bring levels back into a safe range.
Can I eat or drink before the test?
You may eat and drink normally unless instructed otherwise. Some tests require fasting, but digoxin level tests do not.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy