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Test performed at:

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Gentamicin, Post

Test Name

Gentamicin, Post

Red Tube with thin top Specimen Type / Requirements

Container Type = 1 Red Top

Minimum Volume = 3 ml Blood

Tube must fill to at least ½ or greater of its vacuum capacity

Specimen Handling

Collection Instructions: Serum collected in red top tube. Avoid gold top (SST).Serum collected in red top vacutainer without gel separator.

For traditional dosing, collect sample 30 minutes after end of dose infusion. Wait until the 3rd dose before collecting samples for therapeutic monitoring.

For extended dosing, after the 3rd dose collect a sample 8-12 hours after end of dose infusion. Record the exact time of sample and use nomogram for dosage adjustment if necessary.

For further assistance with interpretation contact unit pharmacist.

Record date and time of last dose. Write your initials, date and time of sample collection on the collection label or requisition.

If no time of collection is indicated with the specimen, the test will be ordered as a random level.

Special Instructions Serum free from hemolysis collected without gel separator. Separate samples from cells as soon as possible. Repeated freezing and thawing of samples should be avoided

Rejection Criteria: Gel separator, Unlabeled or Not Sufficient Quantity Samples will be rejected.

Stability: Stable at room temperature for 24h, refrigerated 1 week, frozen 2 weeks (avoid repeat freeze/thaw cycles)

Transportation: Send sample to core lab as soon as possible.

Required Documentation

Turnaround Time

1 hour STAT/Trauma 4 hours routine

Reference Value

For traditional (“conventional”) dosing method.

½ hour post-dose: 4.0 – 10.0 mg/L (pediatrics 5.0-10.0 mg/L)

Toxic: >8.0 mg/L

When used for synergy in the treatment of gram positive endocarditis in adults.

½ hour post-dose: 3.0 - 4.0 mg/L

Test Code



Enzyme Immunoassay

Testing Location


Other Information

Last Updated: December 11, 2019