what are the long term effects of using gravol?

Recently we found out that a family member's health issues were connected to gravol abuse. What are the long-term effects of many years of Gravol abuse and are they permanent?

One of the major problems with chronic gravol use is balance disorders....I went to an ENT because I thought I had fluid buildup in my ears....I was also really off-balance and dizzy....after my ears were perfectly fine...he said that because i had used gravol for years to sleep, it suppressed my balance centers in the brain....takes 3-4 weeks to get back to equilibrium. So, please DO NOT over use gravol! It's so scary to feel this way all the time!!!!

Thanks for the information