Tricyclic Antidepressant (TCA) Screen
Reviewed
This test checks whether tricyclic antidepressants (TCA) are present in your blood or urine and can measure the amount. It is used to help find the right dose, detect misuse, or diagnose a TCA overdose. TCAs are prescription antidepressants that can cause dangerous side effects if levels are too high.
Preparation and collection
No special preparation needed.
Understanding this test
Use the reference interval and units printed by the laboratory that performed the test. A result outside that interval is not a diagnosis by itself, and a result inside it does not rule out every condition. Your symptoms, history, medicines, timing, and related tests can change what the result means.
- Blood test: There is very little risk. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
- Urine test: There is no known risk.
- Results are interpreted by a healthcare professional; reference intervals depend on the specific TCA and clinical context.
What to do next
Results should be discussed with your healthcare provider. If you have symptoms of a TCA overdose, call 911 or go to the nearest emergency center immediately.
Evidence source
U.S. National Library of Medicine: Tricyclic Antidepressant (TCA) Screen