Oral / Sublingual oils are absorbed directly into the blood vessels in the mouth and under the tongue. One should try to wait at least one minute before swallowing. Effects usually start after 10 minutes and peak around an hour and a half after administration. Full effects are reached after about 4 days when CBD has built up and leveled out in your system. For best absorbtion, it is best to avoid eating immediately before or after using a tincture.