Side effect: nausea, vomiting - Tramadol injection (7.3%), Morphin oral (41.2%), Morphin subcutaneous injection (38.3%), Morphin continuous subcutaneous infusion (39.1%), Fentanyl patch (13.6%).
Tác dụng phụ: Buồn nôn, nôn ở Tramadol tiêm (7,3%), Morphin uống (41,2%), Morphin TDD (38,3%), Morphin truyền DDLT (39,1%), Fentanyl dán (13,6%).