Some docs will use Enbrel off label for severe nerve pain from herniated disks. It's not approved by the FDA for this use so you'll have to do a lot of searching and asking to find someone. Try spine surgeons....just call the offices and ask.
I just so happened to be put on Enbrel for RA 5 months after 2 major spine surgeries and it did make the pain go away. However, it didn't help the RA and had unbelievable side effects that made me worse in the long run. So use with great caution if you do find someone to prescribe them. And since it's an off label use, your health insurance won't cover them and they cost about $1500/month for 4 injections.
Most docs won't do it though. Enbrel can kill. It can cause cancer. Herniated disks hurt but they won't kill you.