Diethylstilbestrol (DES) is a hormone classified as a synthetic, nonsteroidal estrogen. It is used primarily for treatment of urinary incontinence in spayed female dogs. It is thought that DES increases the responsiveness of the smooth muscle of the bladder neck to nerve activity, tightening the muscle and preventing leakage of urine. DES is sold by the capsule and expires 6 months from when it is compounded.
