The most common side effects with Soliris (seen in more than 1 patient in 10) are urinary tract infection (infection of the structures that carry urine), nasopharyngitis (inflammation of the nose and throat), upper respiratory tract infection (colds), dizziness, headache, diarrhoea, nausea (feeling sick), back pain, arthralgia (joint pain), pyrexia (fever) and contusion (bruising).