What is correct?
Always take this medicine as your doctor or pharmacist has told you.
Always take this medicine as your doctor or pharmacist have told you.

doctor and pharmacist would be "have", is it the same with d. or p.?
Thank you!

I vote for "has."

And adds up but or doesn't.

So, it's:

A and B have

A or B has

But, it's also:


As or B have

A or Bs have



Some argue that it should be:

As or B has

(That's called the proximity rule.)

There's more on using a plural or singular verb with either/or and neither/nor here.