Decreased heart rate
Decreased heart rate or bradycardia is described as a heart rate that is lower than the normal heart rate at rest. The average healthy human heart normally beats 60 to 100 times a minute when a person is at rest. When the heart rate fluctuates to lower levels under 60 BPM, it is described as bradycardia or an abnormally low heart rate.
It can also be a psychological effect, such as a natural response to feelings of relaxation and serenity. This is a common effect of sedating substances especially depressants such as benzodiazepines or opioids.