The utility of prolactin serial sampling and the best prolactin cut-offs associated with persistent hyperprolactinemia

Approximately 1/3 of the patients reached a normal PRL0'. In an additional 20%, prolactin normalized after serial samplings. Patients with rPRL >53.4 ng/mL had 75% probability of having persistent hyperprolactinemia and those with PRL0' <35.2 ng/mL had a 96% probability of not having persistent hyperprolactinemia.