Flomax side effects

Posted by lifutang @lifutang, Jun 18, 2025

During proton therapy for prostate cancer, I took Flomax to address urinary issues. However, I experienced headache, dizziness, low blood pressure, and even fainted after standing up from a sitting position. I would like to ask if any fellow patients have helpful suggestions for managing these side effects of this medication.

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marc1955 | @marc1955 | May 11 8:11am

In reply to @grandmira "I have been on Flomax 10 weeks, it did what it purported to do, I’m not..." + (show)

@grandmira what kind of eye involvement is implicated with Flomax administration?
Thanks.

grandmira | @grandmira | May 11 9:48am

In reply to @marc1955 "@grandmira what kind of eye involvement is implicated with Flomax administration? Thanks." + (show)

@marc1955
“Intraoperative floppy iris syndrome” which can complicate cataract and glaucoma eye surgery.

stragale | @stragale | May 17 8:51am

My PCP prescribed 1 Flomax per day for me last summer when I started having difficulty starting a urine stream during my nocturnal trips to the bathroom. In September I was diagnosed with prostate cancer. The Flomax helped some but I was still getting up 2-3 time during the night, so my urologist increased the dosage 2 two capsules per day. I started on ADT medication (Orgovyx/Abiraterone/Prednisone) in November, and found that I was getting up even more frequently (4-5 times). My medical oncologist at Cleveland Clinic recommended increasing to 2 capsules twice a day which I understand is the maximum dosage "allowed." I haven't noticed any benefit of the increased dosage, but to the original question, I have not had any side effects of the medication; i.e., no dizziness, no changes in blood pressure, nothing. As my doctors regularly point out, everyone is different and responds differently to different treatments.