Estriol is an endogenous estrogenic steroid hormone with mixed agonist/antagonist activity. Estriol exhibits some anti-inflammatory and antithrombotic activities. Estriol decreases inflammatory cytokine production and improves neuronal pathology and symptoms of multiple sclerosis in clinical settings and in experimental autoimmune encephalitis (EAE) animal models. Estriol induces release of NO through the activation of NOS, causing lysis of platelet-rich plasma and inhibiting platelet aggregation. Additionally, estriol may be used to visualize the prolapsed vitreous body in the anterior chamber of the eye after posterior capsule rupture.