It is an acute form of heat rash associated with excessive sweating, specially humid climate. In Ayurveda, this is known as a type of pidaka.
It consists of small superficial eruption which look like grains of sand. It affects almost any part of the body. Pricking, burning sensation and itching cause a lot of discomfort and may cause secondary bacterial infection.
Chandrakala rasa, kamadugdha rasa, godanti bhasma and chandanasava are the very useful tratment for this condition.