Underarm Sweating
Axillary Hyperhidrosis
Axillary hyperhidrosis is excessive sweating of the underarms beyond what is needed to cool the body. It is a common form of focal (localized) hyperhidrosis, often begins in the teens or twenties, and can occur at rest regardless of temperature. It is benign but can affect daily life, and it is manageable; a clinician can talk through options.
Axillary hyperhidrosis is the medical term for heavy underarm sweating, and it describes a recognized, common pattern rather than a rare disease.
What the term means
“Axillary” refers to the axilla, or underarm, and “hyperhidrosis” means sweating beyond what temperature control requires. Together the term describes excessive underarm sweating that is out of proportion to heat or activity.
It is usually a form of primary focal hyperhidrosis: localized to one or a few areas, not caused by another condition, and often present from a young age. Many people with it sweat symmetrically in both underarms and have done so since their teens.
How it tends to present
The hallmark is underarm sweating that occurs at rest, in cool conditions, and consistently enough to soak clothing and shape everyday choices. It often eases during sleep. Because it is present regardless of the weather, it stands apart from ordinary heat- or nerve-driven sweating.
Why it matters and what helps
Axillary hyperhidrosis is benign (it is not dangerous in itself), but it can weigh on confidence, clothing, and daily life. It is also well recognized and manageable, and a clinician can explain the range of options that fit a given situation.
Frequently asked questions
Is axillary hyperhidrosis serious?
It is not dangerous in itself; it is a benign, common pattern of excessive underarm sweating. But it can affect daily life, and because it is well recognized and manageable, it is worth discussing with a clinician.
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.