Cram-alert (like many others) misses an important point, and is charging for a service that will remain unused.
The place where people make telephone calls, seek advice on your medical history and allergies is in teh A/E department an hour or so after the incident.
At the scene the priorities are different and it is very unlikely that the paramedics will have the time or will prioritise phoning these numbers.
The basic that works is the old fashioned written notes in a Medic-alert or card giving details as these are the things that are looked for.