According to ayurveda sciatica
is called "grudhasi". The blood involvement in this disease plays major role. See all nerves are generated due to sukshma pachan of blood;this is the ayurvedic approval. That means all nervous system is originated by the blood. So that the treatment requires on blood.
1)mahamanjishtadi quath / rasandi quath /panchakol quath with
2)mahayograj guggle /rasanadi guggule /amrutadi guggule etc is highly beneficial.
3)also the diet regulation like mung,puffed rice, old lemon pickle,wheat etc are the basic one. This improves the raktagat (in blood) sukshmapachan and promotes health.
This perfect medication irrespective of any cause ;I have been using in my practice and getting very best permanent results in short time. Hope this will also help you. Have a healthy life soon.