My recovery wasn't typical, as I sustained pituitary gland damage from a whiplash sustained in a rear-end collision. As a result, I had hypopituitarism, along with a concussion. I produced very little growth hormone. I didn't know it at the time, nor was it diagnosed for two years post-accident, so the concussion only minimally healed for the first two years.

When I was placed on growth hormone therapy, I'd say it took about six months to a year for the depersonalization issues to go away. All said and done, I had depersonalization for I'd say 2.5-3 years. Without the hypopituitarism issue, it'd probably have been two years less.