Figure 1: Approach to hyperprolactinemia[1],[20] *When a person does not have any symptoms of raised prolactin, consider ruling out the presence of macroprolactin. It is a big or big-big molecule of prolactin composed of complexes formed by an IgG with monomeric prolactin which is biologically inactive. Thus, assessment of macroprolactinemia by polyethylene glycol precipitation should be performed to confirm true monomeric hyperprolactinemia.[21],[22] †Sometimes, a very large tumor may present with mildly elevated prolactin levels. Here, the prolactin assay should be repeated with serial dilution of serum sample to eliminate the Hook Effect.[20],[23]
![Figure 1: Approach to hyperprolactinemia<sup>[1],[20]</sup> *When a person does not have any symptoms of raised prolactin, consider ruling out the presence of macroprolactin. It is a big or big-big molecule of prolactin composed of complexes formed by an IgG with monomeric prolactin which is biologically inactive. Thus, assessment of macroprolactinemia by polyethylene glycol precipitation should be performed to confirm true monomeric hyperprolactinemia.<sup>[21],[22]</sup> †Sometimes, a very large tumor may present with mildly elevated prolactin levels. Here, the prolactin assay should be repeated with serial dilution of serum sample to eliminate the Hook Effect.<sup>[20],[23]</sup>](articles/2020/68/7/images/ni_2020_68_7_20_287672_f1.jpg)