Very rare side effects These may affect up to 1 in 10,000 people: • hallucinations (‘ seeing’ or ‘ hearing’ things that aren’ t really there) • confusion or agitation • feeling ‘ wobbly’ or unsteady when you move about • uncontrollable body movements (tics), uncontrollable muscle spasms affecting the eyes, head and torso (choreoathetosis), or other unusual body movements such as jerking, shaking or stiffness • a severe skin reaction, starting with a painful red area, developing into large blisters then peeling of layers of skin (toxic epidermal necrolysis) • in people who already have epilepsy, seizures happening more often • changes in liver function, which will show up in blood tests, or liver failure • changes which may show up in blood tests — including reduced numbers of red blood cells (anaemia), reduced numbers of white blood cells (leucopenia, neutropenia, agranulo-cytosis), reduced numbers of platelets (thrombocytopenia), reduced numbers of all these types of cell (pancytopenia), and a disorder of the bone marrow called aplastic anaemia • a disorder of blood clotting, which can cause unexpected bleeding or bruising (disseminated intravascular coagulation)