2 - 5 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Serum or plasma
Red-top tube, lavender-top (EDTA) tube, or green-top (heparin) tube. Do not use a gel-barrier tube. The use of gel-barrier tubes is not recommended due to slow absorption of the drug by the gel. Depending on the specimen volume and storage time, the decrease in drug level due to absorption may be clinically significant.
Transfer separated serum or plasma to a plastic transport tube.
Maintain specimen at room temperature.
Gabapentin (Neurontin®) is an oral antiepileptic agent that is structurally related to the neurotransmitter γ-aminobutyric acid (GABA) but it does not interact with GABA receptors in the brain. Its mechanism of action is unknown but it has properties in common with other anticonvulsant medications. Gabapentin is only 3% bound to circulating protein in the blood and is not appreciably metabolized. Gabapentin is cleared by the kidneys and has an elimination half-life of five to seven hours.1 Steady-state concentrations are reached after one to two days with the time between ingestion and maximal serum concentration being two to three hours.2 For therapeutic drug monitoring, specimens should be drawn as trough levels. There are no significant drug interactions with other anticonvulsants. Adverse reactions are not common and are confined to somnolence (1.2%), ataxia (0.8%), fatigue (0.6%), nausea or vomiting (0.6%), and dizziness (0.6%).
|Order Code||Order Code Name||Order Loinc||Result Code||Result Code Name||UofM||Result LOINC|
|716811||Gabapentin (Neurontin), Serum||9738-6||716812||Gabapentin, Serum||ug/mL||9738-6|
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