Following a concussion, the first 24 to 48 hours are very important, because in some cases, there is potential for a more serious injury that may require immediate medical attention. This could include swelling or bleeding in the brain. While it is safe to take a nap or sleep after a concussion if there are no other symptoms present such as dilated pupils, difficulty holding a conversation or trouble waking, the person with a concussion should be observed closely by an adult for at least 3 hours following the injury. The objective here is to monitor the individual for any signs or symptoms of a worsening condition. This could be indicative of a more serious injury to the brain.