ID is a matter of life or death and a necessity for anyone having any medical conditions especially allergies to drugs.
In my many years serving on the First Aid Squad, an ID such as a pendant, wristlet, something visible is one of the first things to look for when assessing a person’s condition.
There are locations that will provide a free pocket or wallet info card. The biggest problem with a wallet card is also the reason for their popularity their hiddenness. There are other discrete but open avenues available. On this page there are other helpful links.
There is a service that will have an electronic history and ID. Having your loved one wear an ID can give great peace of mind to you by having greater assurances of reducing any errors if there is any need for emergency treatment.This picture will link to another site to help when you may not be able to speak or prefer another method for help-