How Long Does Excessive Sleepiness Take To Get Cured When On Antibiotics?

Hi My mother has been in hospital three months after a operation for adhesions in the bowel. She has been fed by TPN and recently developed a fungal infection so they had to stop the TPN - after 10 days they have started and now she has pneumonia. Her potasium levels are low and she is very very sleepy. The doctors are testing her blood regularly and she is on two types of antibiotics. How long will it be before she becomes less sleepy?