from my understanding there's a Sealing arrow, and a Sacred arrow.
Sealing is what kikyo used, its meant to bind to the shooters power and will. I.E. Kikyo while she knew she was dying sealed inuyasha to the tree knowing that only SHE could release him. But she was dying. Basically she put him into ever lasting sleep.
While a Sacred arrow would be the demon killing kind, well harming, obviously depending on the power behind the arrow and the demon its shooting results very. IE. pissy kagome shoots Seshsomaru and breaks his jyaki infused armor, vs. REALLY pissy kagome blowing up all of Naraku but his head b/c she's got bad aim.