You are given pain medications during surgery and in your recovery process. These include: Pills Intravenous medication Pumps Post-operative pain is caused by injury to your skin, muscles, bones, and nerves during the operation. It is important to manage your pain because it will interfere and slow your recovery process such as breathing, sleep, appetite, and activity. For example: Breathing: Pain can prevent you from taking deep breaths. Shallow breaths increase risk for pneumonia. Sleep: Inadequate pain control affects your comfort and rest. Appetite: Inadequate pain control may affect your desire to eat. Activity: Inadequate pain control may affect your ability to get out of bed, move, and walk. The amount of pain medication you need depends on your pain tolerance and your response to the medication given. For your safety, your doctors and nursing staff monitor the amount of medications you are given. Although significant amount of pain medications are given, they may not completely stop your pain, but it should keep the pain at a level that allows you to move, eat, and breathe easily.