Dextran 70 (Hyskon) solution, as many other substances, is in current use as distension medium during hysteroscopy. The advantages of Hyskon solution are its nonconductivity and immiscibility with blood, allowing good visibility during operative hysteroscopy. Adverse reactions to Hyskon are mainly attributable to the drug’s antigenic properties and include severe anaphylactic reactions and fatalities. We report a case of anaphylactic shock during hysteroscopy using Hyskon solution as the distension medium, review the adverse reactions of Hyskon and summarize the treatment modalities used to decrease the incidence of the rare but serious adverse reactions with its use.