Jack was looking at her "force it to eat a lemon, should weaken it," he explained "Though that way is messy as will make it unwell." He makes a face. "But if its weakened in anyway it will let go. Well I don't know if any ways the Doctor won't disaprove of."
He shrugged a bit.
The Doctor was breathing weakly, the creature still having firm grip on him. 
He rolled over a bit and fell onto the floor.