Priapism happens sometimes, and Flomax
has been known to cause it as a side
is not unique with this side
effect. Drugs that can cause it most often are antihypertensives, antipsychotics (e.g., chlorpromazine, clozapine), antidepressants (most notably trazodone), anticoagulants.
Your drug list, spelled correctly, is: Flomax, morphine, Phenergan, lorazepam, ibuprofen, Prilosec, and doxycycline if you want to read up on them individually.