Hello. Your test project is online here: test.haxa.tk. Press List button to see the values that are currently exist. Note that "Save" button will overwrite the whole list so you can't append to the current values with the "Add New Remedy" button, it's only useful when creating a new list.
To make things fast, I've avoided a combobox for user to select from. You can input symptoms in the same way that saving remedies, by comma separation. Contact me from chat if something doesn't work in your case or you think it's not working, this was a very fast adaption.
I have free trial accounts on all major cloud services so I can adapt it to any database/service you want. Worked with Google Cloud Firebase, Equivalent Microsoft Azure services and many more in the recent years. But I don't have any clue about IoT.
I'm very good with back end communications like AJAX, REST, HTTP Long Polling, Websockets and pretty much everything related to them. So if the devices you use also works on those standards, then I might help.