Succinylcholine can cause:

Administration of succinylcholine to an otherwise well individual for an elective surgical procedure increases plasma potassium levels by approximately 0.5 mEq/dL. This increase in potassium is due to the depolarizing action of the relaxant. With activation of the acetylcholine channels, movement of sodium into the cells is accompanied by movement of potassium out of the cells. Ref: Miller's anesthesia-7th ed, Chapter 29.