Ensure that the patient has abstained from medications (upon the advice of physician) for at least 72 hours before collecting sample.
Medications that may affect results include mao inhibitors,
methyldopa, morphine, reserpine, and lithium.
Allow serum separator tube (SST) contents to clot in an upright position for at least 30 minutes.
Centrifuge within 2 hours of collection.
Label a plastic transport tube with two identifiers. Acceptable identifiers include patient’s name, date of birth, social security number, requisition number, and medical record number. Label the tube as serum.
Transfer serum to the tube and freeze - send this aliquot separately when multiple tests are ordered.