What Causes Dizziness And Blackout While Being Diagnosed With Vertigo?

My husband is 56 years old. He is in good health but a year ago, after alot of test & an MRI which was clear, he was diagnosed with vertigo, ringing in the ear & possible beginning stages of manieres disease. He has been less consistent lately with his medications & excercises for vertigo/manieres. Two days ago as he got out of bed early that morning, he was a bit dizzy & blacked out for a few seconds. Is a blackout typical for someone with vertigo or manieres or should he be further tested?