How long does labyrinthitis usually last?

1-4 weeks. Anywhere from 1-4 weeks. Sometimes residual dysequilibrium for several months. Neurosensory hearing loss is almost always permanent.
Depends. Labyrinthitis has become a "grab-bag" word for dizziness. A true labyrinthitis usually begins with sudden onset of whirling vertigo. This acute incapcitating vertigo continues for 24-48 hrs. This followed by 2-10 days of severe disequilibrium mixed with motion induced vertigo. Over the next several weeks it slowly improves with normal walking at about 6-8 weeks with flareups for 6 months.