The most common side effects with Reblozyl in patients with myelodysplastic syndromes (which may affect more than 15 in 100 people) are tiredness, diarrhoea, weakness, nausea (feeling sick), dizziness, back pain and headache. The most common serious or severe side effects (affecting more than 2 in 100 people) include syncope (fainting), tiredness, hypertension (high blood pressure), weakness, urinary tract infection (infection of the structures that carry the urine) and back pain.

The most common side effects of Reblozyl in patients with beta thalassaemia requiring transfusion (which may affect more than 15 in 100 people) are headache, bone pain and joint pain. The most common serious or severe side effects are hyperuricaemia (high levels of uric acid in the blood), stroke, effects due to blood clots in the veins such as deep vein thrombosis, portal vein thrombosis (clots in the veins supplying the liver) and pulmonary embolism (clots in the veins supplying the lungs).

The most common side effects of Reblozyl in patients with beta thalassaemia not requiring regular transfusion (which may affect more than 15 in 100 people) are headache, bone, back and joint pain, and prehypertension and hypertension (high blood pressure). The most common serious or severe side effect is traumatic fracture (a fracture caused for example by a fall or an accident).

Reblozyl must not be given during pregnancy. Women who can become pregnant must use effective contraception during treatment and for at least 3 months after the last dose. Patients requiring treatment to control the growth of extramedullary haemopoiesis masses (the formation of blood cells outside the bone marrow) must not use Reblozyl. For the full list of side effects and restrictions of Reblozyl, see the package leaflet.