Why does valafaxine hydrochloride make ejaculation and orgasm difficult in men?what does it do in the brain to cause these problems? new user curious.

Serotonin: Sexual dysfunction with medications like venlafexine is common. The cause is the blockage of the reuptake of serotonin between nerve cells. The symptoms aren't due to impact on the brain, it's the way serotonin is affected in the male genitals. It can blunt sensation, making ejaculation difficult. Talk to the prescribing doctor about this troublesome side effect.