Hello,
Flomax is used for the treatment of BPH and if you are having side effects to this drug then you can use other alpha blockers like doxazosin, terazosin,
alfuzosin or 5 alpha reductase inhibitors like finasteride and dutasteride.
Effects may take longer to appear than alpha blockers, but they persist for many years. But they are available under prescription and should always be taken under a medical guidance.
I sincerely hope that helps.