You will need to take your test about three to four hours after waking up. Prolactin levels change throughout the day, but are usually the highest in early morning.

Can prolactin test be done during periods?

You can have your prolactin levels checked at any point in your menstrual cycle. Prolactin levels vary throughout the day but are highest while you are asleep and first thing in the morning, so the test is usually done about three hours after you wake up.

Is fasting required for prolactin blood test?

The prolactin test is typically ordered to diagnose galactorrhea, or abnormal lactation, but can also be useful in the diagnosis of headaches and visual disturbances. Fasting is not required for this blood test, and results will be delivered within 1-2 days. The Prolactin Serum Test may also be referred to as PRL.