An Unusual Suspect: Hyperprolactinemia From Nicotine Pouches

Elevated prolactin levels are associated with galactorrhea, menstrual irregularities, or infertility. While nicotine is known to affect prolactin secretion via dopaminergic pathways, noncombustible nicotine products such as pouches are rarely considered as contributing factors. The objective of this report is to describe a patient with hyperprolactinemia associated with nicotine pouch use, highlighting a potentially overlooked etiology.

A 21-year-old woman with a history of attention deficit hyperactivity disorder and bipolar disorder presented with infertility after 12 months of trying. She had discontinued oral contraceptives and risperidone 1 year prior, as she wanted to start her family, with improvement in breast engorgement and galactorrhea over the last 12 months, she reported regular menstrual cycles. She had quit smoking 2 to 3 weeks prior to having her prolactin levels checked and had started using 10-12 nicotine pouches daily (6 mg each) to help with nicotine cravings. Initial labs showed a prolactin level of 312 ng/mL (reference: 5.2-26.5 ng/mL), thyroid-stimulating hormone 1.18 uIU/mL (0.40-4.00 uIU/mL), and β-human chorionic gonadotropin <2 mIU/mL (reference: <5 mIU/mL).She discontinued nicotine pouches immediately after seeing high prolactin levels, and prolactin levels normalized 2 and 3 days later (13.4 ng/mL, then 8.8 ng/mL, respectively).

Nicotine may increase prolactin by inhibiting dopamine's regulatory effects. While this is documented in smokers, its impact via nicotine pouches is less well studied.

This case highlights nicotine pouch use as a possible cause of hyperprolactinemia. Clinicians should consider alternative nicotine products when evaluating patients with unexplained hyperprolactinemia.