Commonly, pain relief in the first few days after surgery is provided by epidural analgesia. Drugs are delivered to the area around the spinal cord, through a fine plastic tube placed in the patients back, and this blocks sensation from the abdomen downwards, thereby providing effective pain relief without the need for opiate analgesia (e.g. morphine). Opiate analgesia can cause nausea, drowsiness and constipation, and its use should be minimised. Epidurals, however, can be associated with some problematic side effects. Low blood pressure is commonly encountered, and not only can its treatment be associated with complications, but patients are often confined to bed.