Tropical Climates:
The people living in hot and humid weather can cause more chances of heat rash.
Intense physical activity:
Doing an intense and hard exercise or playing a sport that causes more amount of sweat production can also lead to cause heat rashes in the people.
Prolonged bed rest:
The people who confine themselves to bed for long periods due to some injury or disease are also at higher risks of developing heat rash more often.