Intravenous infusion of sodium bis(alginate) can cause ischemic abnormal penile erection. The local hyperviscosity of blood in the penile corpus cavernosum after sodium alginate infusion may be the pathogenesis of ischemic abnormal penile erection. Conservative treatment is often ineffective and should be performed as early as possible with penile corpus cavernosum aspiration, lavage or penile head cavernosal shunt.