How much time does one generally have pain, specifically nerve pain with sciatica?

4-6 weeks: Initially the symptoms last 4-6 weeks and if your body heals like it supposed to then pain relief starts. However disc herniations which are the cause of majority of sciatica symptoms last for 6-9 months and therefore people can have pain during that time as well. If not better after 6 weeks see a spine specialist to evaluate this further.

Depends: It all depends if the cause remains inflaming the nerve. It can take weeks months to even years. Oral or injected steroids can help.