Marcain (generic name: bupivacaine hydrochloride) is used as an anaesthetic agent, particularly when long-term anaesthesia is required eg. during surgery and during child birth. It is often used in epidural anaesthesia & also used for postoperative pain management and for pain management in some other medical settings.
It belongs to a group of medicines called spinal local anaesthetics. They are injected into the spinal fluid where they make the nerves unable to pass messages to the brain. Depending on the amount used, you will either totally stop pain or will cause a partial loss of feeling.