As it turns out, oleander extract is used in Russia for treating vertigo.  Of course, you want to either use a recognized oleander supplement or else prepare your own by following exact instructions, as oleander in unprepared raw form is toxic.  See:

The Recipe for Oleander Soup Part 1

The Recipe for Oleander Soup Part 2 - Tips and Advice

Also, here is a home/herbal remedy I have on file which might help:

• Mix 7 to 8 almonds with 7 to 8 kernels of pumpkin seeds, one teaspoon poppy seeds and three tablespoon wheat. Soak in water overnight.

• Next morning, remove the outer skin of the almonds and grind everything together into a fine paste. Heat separately two teaspoon ghee and fry ½ teaspoon cloves. Add the paste to it along with some milk and boil the whole mixture.

• Sweeten with honey (preferably raw organic honey) and drink every day for a few days for vertigo relief.