I think an enlarged prostate can cause no erection at all and/or an erection for short periods of time, right? Does it also cause you to lose your libido/interest in sex completely?
Thanks for your question. You might want to check out our section on Enlarged Prostate / BPH. The article on the symptoms of BPH actually does not mention these sorts of sexual side effects that you list, though that does not mean they aren't linked.
The loss of sexual urges may also simply be linked to a decreased testosterone level, something that happens naturally as the male body ages.
Untreated BPH (prostate enlargement) is not associated with a lack of erection. On the other hand, BPH is a disease of older men, and impotency also occurs with greater frequency in older patients. BPH and ED do coexist in many patients however there is no cause/effect relationship.