CBD is not psychoactive.  This means that it does not change the state of mind of the person who uses it.  However, it does appear to produce significant changes in the body and has been found to have significant benefits.
The World Health Organization has recognized CBD as safe, non-toxic and with very few side effects.
All of these methods of using CBD oil work well because our bodies have two cannabinoid receptors. These receptors send information to activate other receptors, such as the vanilloid, adenosine and serotonin receptors. This causes our bodies to release various neurotransmitters, in turn relieving pain and improving mood.
Although CBD is extremely effective, the amount of time it takes to feel the effect varies depending on the individual, the ailment being treated, and the form of CBD oil they are using.  CBD oil can be used orally, topically, or inhaled as vapor.
Vaping is the quickest option and covers all the bases of ailments, as it is disbursed through the bloodstream.  Orally dropping the oil you can expect anywhere from 20 to 40 minutes before the CBD will take effect -- but it will also cover a large range of ailments.  Topically, on the other hand, is used for spot-specific skin issues and will take somewhere around an hour to take effect.