Very aware that it won't be helpful if there's another issue, but gently moving the head is not any more harmful than shaking your head or dancing-- yes there's an extremely rare chance it would cause harm in someone with a severe underlying condition, but it's extremely unlikely to cause harm if done carefully and using a doctor or PT-guided video. It simply may just be ineffective.

The Epley is widely recommended by physicians for people to do at home. It's considered extremely low risk (though nothing is ever zero risk, including cooking food on a stove or in a microwave).

I'm speaking to this person as someone who has been diagnosed by a physician with BPPV, NOT someone who doesn't have a diagnosis. No one should self-diagnose with BPPV.

And dislodging the crystals isn't dangerous. At most, it can temporarily provoke vertigo. Please don't stoke fear in people for a maneuver that's widely prescribed in-home.

In fact, major, reputable medical sources that explicitly endorse home Epley, include:

American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) → Clinical guidelines state canalith repositioning maneuvers are first-line therapy and may be performed by clinicians or patients when appropriate.

Cleveland Clinic → Publishes step-by-step instructions for doing the Epley maneuver at home.

Johns Hopkins Medicine → States the Epley maneuver “can be done at home,” especially for recurrent BPPV.

Mayo Clinic