Salicylate
At a Glance
Why Get Tested?
To monitor aspirin therapy of inflammatory disease such as rheumatoid arthritis to guard against overdosage, and to guide hospital treatment if aspirin overdosage is suspected
When to Get Tested?
At least 3 hours after the last dose of aspirin
Sample Required?
A blood sample drawn from a vein usually in an arm
The Test Sample
What is being tested?
The plasma concentration of salicylic acid (the active part of aspirin) is being measured as this produces the undesirable side effects, notably damage to the stomach, including ulcers and bleeding, and tinnitus (ringing in the ears).
How is the sample collected for testing?
Normally from a vein in the arm by use of a needle and syringe.
The Test
How is it used?
The plasma salicyate concentration is used to assess aspirin dosage and, if overdosage is diagnosed, to guide hospital treatment of aspirin poisoning.
When is it requested?
Either to monitor dosage during long-term aspirin treatment, or to help diagnose overdosage.
What does the test result mean?
During long-term aspirin treatment of rheumatic fever, rheumatic arthritis, and other inflammatory joint conditions, the plasma salicylate concentration is normally between 250 and 300 milligrams per litre (mg/L). After overdosage the result has to be interpreted by the hospital doctor who takes into account other factors such as the time the overdose was taken and whether other drugs are present
Is there anything else I should know?
Aspirin should not be taken long-term without consulting your doctor and should NEVER be given to children under 16 years of age unless directed by a doctor. Aspirin should not be taken with alcoholic drinks as this increases the risk of bleeding from the stomach. If aspirin overdosage is suspected you should seek medical help. Ibuprofen (Neurofen) or paracetamol (Panadol) are safer treatments than aspirin for short-term problems such as headache.
Common Questions
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