With sciatica that is irritated vata (stress). Major need is to relax, eat and sleep consistently. Most common need is to strengthen the external hip rotators you can look in my book for examples of what does that I find doing sunbird with leg turning outward is often best way to do this. Gentle backbends like cobra and locust, which focus on strength and not stretch, can help. Also avoid contraindicated motions, which are all forward bends. Especially do not stretch hamstrings. For more chronic issues a colonic or enema may be helpful too. The seat of the problem is often colon issue – diet irregularity, too much travel, or suppressed fear. This is such a common problem you will see many questions on this topic – so do a search under sciatica at my Website www.yogaforums.com for more ideas.