Reference
Intertrigo
Intertrigo is irritation and inflammation that develops in skin folds where surfaces rub together and moisture collects. Warmth, friction, and trapped sweat combine to inflame the skin.
What intertrigo means
It commonly appears in areas like the underarms, under the breasts, the groin, or abdominal folds. Sweat that cannot evaporate in these enclosed spaces keeps the skin damp, which encourages redness and soreness. Rubbing between skin surfaces adds friction that worsens the irritation. Keeping folds cool and dry is often discussed neutrally, and persistent or worsening cases may need medical care. Warm weather and heavy sweating can make it more likely, since both add to the moisture in the fold. When the damp skin also softens over time, it becomes more prone to breaking down. The name comes from roots meaning to rub between. The three ingredients of warmth, friction, and moisture are what set it apart from other rashes. It tends to appear exactly where two skin surfaces press together and trap sweat.
In practice
Redness and soreness that develop under a skin fold during a hot, sweaty stretch of weather illustrate intertrigo. The combination of two skin surfaces pressed together, trapped sweat, and constant rubbing is what turns an ordinarily hidden fold into an irritated one. It commonly shows up under the breasts or in the groin, where folds are deep and sweat lingers.
Frequently asked questions
Where does intertrigo tend to appear?
In skin folds such as the underarms, groin, or under the breasts. These are places where warmth, friction, and moisture gather together.
Why does sweating make intertrigo worse?
Sweat trapped in a fold cannot evaporate, so it keeps the skin damp. That added moisture increases the friction and irritation.
Sources & further reading
The reputable organizations our editorial team draws on for the anatomy, definitions, and safety guidance behind this page, and where you can read more on each topic.
General educational information about sweating. Not medical advice, and not a substitute for diagnosis or treatment by a qualified healthcare professional.