In simple words: Heat rash, also known as prickly heat, is a common skin irritation caused by excessive sweating. It appears as small, red bumps that can be itchy or prickly.

Miliaria rubra, commonly known as heat rash, is a skin condition characterized by small, itchy, red bumps that appear when sweat ducts become blocked.This blockage traps sweat beneath the skin's surface, leading to inflammation and the characteristic rash.It frequently occurs in hot, humid weather.

Example 1: A 2-month-old infant presents with small, red bumps on their neck and back during a heatwave. The infant is diagnosed with miliaria rubra., An athlete develops itchy, red papules on their chest and back after intense training in hot and humid conditions.This is diagnosed as miliaria rubra., An individual on bed rest due to a medical condition develops miliaria rubra on areas where sweat accumulates, such as under the breasts or in skin folds.

Documentation for L74.0 should include a description of the rash's appearance (e.g., location, size, color of the bumps), associated symptoms (e.g., itching, burning), and any precipitating factors (e.g., hot weather, excessive sweating, occlusive clothing).Relevant history such as recent activity, environmental conditions, and past episodes of similar rash should also be noted.