You shouldn't IV ambien, there's no real benefit to doing so. If you know what form of zolpidem you have, and you've got some sterile supplies, you have a fighting chance. Otherwise, don't bother.
Zolpidem tartrate could theoretically be injected. Use a micron filter and sterile supplies. Same as any other IV pill.
Zolpidem freebase will not dissolve in water and is not injectable.
Hold the pills under your tongue if you want themto work faster.