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Primary hyperhidrosis and thoracic sympathectomy
Primary focal hyperhidrosis (palms, axillae, face) begins in childhood or adolescence, is symmetrical and disappears during sleep; it is first treated with topical agents, iontophoresis and botulinum toxin, and in selected patients with severe palmar sweating bilateral VATS interruption of the sympathetic chain is done — highly effective, but with a significant risk of compensatory sweating.
Why it matters in the exam
Distinguishing primary from secondary hyperhidrosis is the first step: primary sweating is focal, symmetrical, begins before age 25, does not occur in sleep and sometimes has a family history; generalised, unilateral or nocturnal sweating, or sweating first appearing in an adult, needs work-up for a secondary cause — hyperthyroidism, diabetes, infection, lymphoma, phaeochromocytoma or drugs. Conservative treatment in order: topical aluminium chloride, tap-water iontophoresis (especially effective for the palms), botulinum toxin injections (especially effective for the axillae) and oral anticholinergics such as glycopyrrolate or oxybutynin.
Surgery — division or clipping of the sympathetic chain by bilateral VATS — suits mainly severe palmar sweating that has not responded to conservative treatment. According to the STS consensus (2011) the level is chosen by region: for the palms — R3 or R4 (division over the third or fourth rib); for the axillae — R4 and R5; for facial sweating and blushing — R2, which carries a higher risk of compensatory sweating and Horner syndrome. Palmar success is very high, above 95%. The main and common complication is compensatory sweating of the back, abdomen and thighs, which may be worse than the original problem; it is more common with higher and more extensive division, so it must be explained before surgery. Other complications: Horner syndrome from injury to the stellate ganglion (R1), pneumothorax and bleeding.
Axillary sweating alone is first treated with botulinum toxin or topical treatment, and surgery is kept for selected cases.
Key points
- Primary — focal, symmetrical, not in sleep.
- Conservative first: topical, iontophoresis, botulinum.
- Palms — R3 or R4.
- Compensatory sweating — the main complication.
- R1 — Horner.
Summary table
| Region | Main conservative treatment | Surgical level | Note |
|---|---|---|---|
| Palms | Iontophoresis, aluminium chloride | R3 or R4 | Success above 95% |
| Axillae | Botulinum toxin, aluminium chloride | R4 and R5 | Surgery for selected patients |
| Face and blushing | Oral anticholinergics | R2 | High risk of compensatory sweating and Horner |
| Generalised or nocturnal sweating | Look for a secondary cause | — | Not for surgery |
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Sources
- STS expert consensus for the surgical treatment of hyperhidrosis, 2011 — Levels of sympathetic interruption and outcomes
- Canadian Hyperhidrosis Advisory Committee: Treatment algorithm for primary focal hyperhidrosis, 2007 — Recommendations
- Shields' General Thoracic Surgery, 8th edition (2019) — Thoracic sympathectomy
Sources are given for further reading; the text is written afresh and not copied from them.
Reviewed by the Examqo AI Professor · 2026-11-06. The text may contain errors; when in doubt, check the source.