A general power of attorney is a power of attorney designated for a specific period of time when the grantor will be unable to make financial decisions or advocate for their medical needs.
A durable power of attorney, on the other hand, allows the principal to make their own decisions up until the point that they're unable to. This could be when old age renders them unable to, or if they have an unexpected medical issue that doesn’t allow them to understand treatment options or consent to specific ones they want.