Or what would that be called?
For example, not believing someone about their health issue, refusing to believe that it impacts their ability to function or can be a valid excuse for things, often solely on the basis that it’s not a recognised disability, and/or claiming that their opinions can’t be taken seriously due to their health problem?
Are you asking regarding employment, or just in society at large? In the US, there are laws outlining what constitutes employment discrimination, and I don’t think you’ve given us enough detail to say more.
I’m curious what you mean by “not a recognized disability?” Recognized by whom? Someone with a health condition that impacts their ability to function in one or more life domains is certainly experiencing a disability