You can disable the button in your action method when it receives the first tap. Alternatively you can just ignore the second tap while it's doing something.
Thank you for your reply, although your answer would be helpful during certain scenarios that I might encounter; it interferes with other code that I might wish to implement in the button and the graphical user effect is not quite suitable. I found another snippet of code that I thought I should share because it works nicely: it controls the responsiveness of a particular button without affecting the entire button code
Code:
self.buttonname.isUserInteractionEnabled = false
A modified version of this code snippet can affect the whole view controller after pressing a particular button