While most people who undergo Reiki feel uplifted and comfortable after a session, some people experience a "healing crisis."
Toxins contained in the body are released into the bloodstream, purified by the kidneys and liver, and eliminated from the system as an individual's vibration rises.
As a result, a person can feel tired, have a stomachache, or have a headache.
Practitioners also advise clients who are experiencing mild side effects to drink more water, get more rest, and consume lighter meals. The washing of the body is an essential aspect of the Reiki therapy.
You may also want to read more about Reiki Healing here.