I've had numerous BPPV episodes and Foster's half somersault maneuver works beautifully.
If it is BPPV avoid looking up or tilting your head back for any length of time, at least for me, that causes the crystals to move into the wrong part of the inner ear - hence vertigo.
This site is run by Ivar at in Santiago de Compostela.
This site participates in the Amazon Affiliate program, designed to provide a means for Ivar to earn fees by linking to Amazon