I don't know about that other test. That level seems high but keep in mind I am a patient like you.
Repeat tests should be done not really for error but just to see, as well as other pituitary hormones.
Thanks. Can I know if prolactin level of 639.7 micro U/ml. is to high / cause of panic for a non pregnant women? Is repeated blood test necessary to rule out any error? What is "polyethylene glycol precipitation prolactin test"?
You should see a competent endocrinologist.
First, prolactin can be raised by many things other than a prolactinoma, like medications, thyroid etc. so you have to get someone to rule in and out all causes.
You will probably need a few blood tests and a scan and the scan should be done properly. You don't need an MRI that often. MRI should have been with and without contrast and dynamic method to best show any lesion.
As for the medication, like many, they are used for multiple disorders and usually the dosages that treat a prolactinoma are low and not in the range that are damaging (but some people like for any med can be more sensitive) so as a patient I would guess the risk the lower since dose is low side.
Sorry no OTC or herb will help. Best if you find a pituitary center so you are treated most appropriately. Large hospitals or university centers will have one.