Although it is important that everyone's intentions are positive when a treatment is conducted to avoid drawing negative energy into it, reiki has no measurable adverse effects on people. However, this does not mean that it is always appropriate to pursue the practice. For example, involving minors in treatments should be undertaken with an additional layer of care which means that sessions will often be much shorter and less intense than they otherwise would be. The same goes for other vulnerable groups who may not be able to always advocate for themselves effectively. Sometimes, practitioners are criticised for treating people who have chronic or life-changing conditions because they are seen as undermining their conventional medical treatments. Although the practice has no known effect in this regard, it may be the right thing for practitioners to sometimes step away temporarily. Because of the way it affects people, patients should be calm and relaxed during treatments and certainly not performing a task, such as driving, for example.