An anaphylactic emergency that has happened in the workplace would be recorded in the accident book, and you do need to make sure that the correct accident records are kept. This would be the standard accident book in your workplace. You would document who has had the problem and you would also write down in the book what treatment they've had and who put the information in there. You'd also need to follow general policies within your company. If you're unsure about this, talk to your manager. There may be a separate medications record of who has them and what exactly they have. Also, if you deliver any medications, you may need to record this separately.
If your organization is an “authorized entity” that is permitted to have undesignated auto-injectors on-site, you may also be subject to additional reporting requirements by your state if an auto-injector has been administered. Please refer to your local state laws for details on how to file a report.