A CBD tincture is a preparation of CBD in a carrier oil, which can be olive oil, hemp seed oil, or coconut oil to name a few. Tinctures are administered under the tongue (sublingually), held for at least 90 seconds, then swallowed. Since tinctures are used sublingually, CBD is absorbed directly into the bloodstream through the capillaries located in the mouth. CBD tinctures are very fast-acting, and an effective method for taking CBD.