I have a relative in their 80s who has been type 1 for 30 years. However recently they are becoming more confused. Are there any insulin pens that store dosage given? Monitors store readings. However to get the full picture I want to check the units of insulin that they are administering.
There are the Novopen 6 and novopen echo (half units) pens that show the units taken and how long ago, but it's for the novodisk insulin cartridges. I assume other insulin brands do something similar. BG meters will always store readings. You'd need to ask their diabetes team about it.