Sweat injections for hyperhidrosis
Underarm, palm and scalp ('blowtox') neuromodulator for sweating
'Blowtox', scalp injections to keep a blow-dry through workouts, revived interest in sweat injections among people who never thought of themselves as having hyperhidrosis, alongside the long-standing medical use for underarms and palms.
Search interest: about 150 searches a month in Singapore for “hyperhidrosis treatment” (Ahrefs, October 2026).
If sweating stops you shaking hands, this is one of the few treatments in aesthetics with level I evidence; if it only threatens a blow-dry, that is a different conversation.
Reviewed against the Aesthetics International standard. Category: Injectables.
Do Sweat injections for hyperhidrosis work?
Established. If sweating stops you shaking hands, this is one of the few treatments in aesthetics with level I evidence; if it only threatens a blow-dry, that is a different conversation. Axillary hyperhidrosis has level I evidence: a 2025 meta-analysis of twelve randomised trials found a large reduction in gravimetric sweat against placebo, equivalence with other treatments and fewer side effects.
- Verdict
- Established Long clinical track record. Results depend on selection and technique more than on the device.
- Evidence base
- 3 PubMed-indexed studies cited below, including systematic reviews.
- Suits
- Primary focal hyperhidrosis of the underarms, palms or soles that has not responded to antiperspirants; craniofacial sweating that affects daily life.
- Not for
- Generalised or secondary sweating, which needs a medical cause excluded first; people who need fine hand strength for their work in the weeks after palm treatment; cosmetic scalp treatment in someone who simply sweats normally when exercising.
- In Singapore
- Botulinum toxin products are prescription-only medicines in Singapore, prescribed and injected by doctors; axillary hyperhidrosis is a licensed indication and other sites are off-label.
- Category
- Injectables · about 150 searches a month in Singapore for “hyperhidrosis treatment”
- Reviewed
- 1 October 2026 by Aesthetics International. Revised as evidence and regulation change.
What it is
Botulinum toxin, a prescription medicine, injected in a grid of shallow points across sweating skin. It blocks the nerve signal to eccrine sweat glands for four to twelve months. Underarm treatment is a licensed indication; palms, soles, face and scalp are off-label uses with their own evidence.
How it works
Sweat glands are driven by acetylcholine, the same transmitter the toxin blocks at the muscle. Shallow intradermal placement reaches the glands without weakening muscle, except in the hands, where some diffusion to the small muscles is hard to avoid. A starch–iodine test maps the sweating area so the dose goes where it is needed. Scalp and face need many points and careful dosing to avoid brow weakness.
What the evidence says
Axillary hyperhidrosis has level I evidence: a 2025 meta-analysis of twelve randomised trials found a large reduction in gravimetric sweat against placebo, equivalence with other treatments and fewer side effects. Palmar treatment has a randomised trial and consistent series showing relief, limited by injection pain and transient grip weakness. For the scalp and face, a 2026 systematic review found only small cohorts and case series, reporting meaningful improvement with heterogeneous dosing. 'Blowtox' for cosmetic convenience in people without hyperhidrosis has no evidence beyond the mechanism.
What people are saying
Paraphrased from public discussion on TikTok, Instagram, Reddit and in the press. Not testimonials, and not about any one clinic. Reported in: wellandgood.com, fastcompany.com.
What the studies show
- systematic review
Twelve RCTs in 904 patients showed botulinum toxin reduced axillary sweat production more than placebo, matched other treatments on sweat reduction and pain, and caused fewer side effects.
Efficacy and Safety of Botulinum Toxin Type A in Primary Axillary Hyperhidrosis: A Meta-analysis and Systematic Review — Aesthetic Plastic Surgery, 2025. PMID 40500510.
- systematic review
Few good-quality studies exist for palmar hyperhidrosis; one randomised double-blind trial of botulinum toxin reported improvement in 90 per cent of patients, alongside evidence for iontophoresis and anticholinergics.
The treatment of palmar hyperhidrosis - a systematic review — International Journal of Dermatology, 2022. PMID 34653261.
- systematic review
Evidence was strongest for the axillae and reliable for the palms, while craniofacial and scalp treatment rested on small cohorts and case series reporting meaningful improvement with heterogeneous dosing.
Beyond the axilla: The evolving role of botulinum toxin in the treatment of facial, scalp, and focal hyperhidrosis — Clinics in Dermatology, 2026. PMID 41461243.
Studies are selected for relevance and quality, not for agreement with the verdict; PubMed records are linked so the reader can check them.
Who it suits
Suits
Primary focal hyperhidrosis of the underarms, palms or soles that has not responded to antiperspirants; craniofacial sweating that affects daily life.
Not for
Generalised or secondary sweating, which needs a medical cause excluded first; people who need fine hand strength for their work in the weeks after palm treatment; cosmetic scalp treatment in someone who simply sweats normally when exercising.
Alternatives
The two reviewed treatments most often weighed against Sweat injections for hyperhidrosis, on the same standard.
| Sweat injections for hyperhidrosis | PDRN and polynucleotides | Profhilo | |
|---|---|---|---|
| Verdict | Established | Established | Established |
| What it is | Botulinum toxin, a prescription medicine, injected in a grid of shallow points across sweating skin. | Polynucleotides are DNA fragments, usually purified from salmon or trout gonads, injected into the dermis in micro-droplets. | A high-concentration, stabilised hyaluronic acid injected at five points on each side of the face (the BAP technique), from which it spreads through the tissue. |
| Evidence base | 3 PubMed-indexed studies cited below, including systematic reviews. | 3 PubMed-indexed studies cited below, including systematic reviews, randomised trials. | 3 PubMed-indexed studies cited below, including randomised trials. |
| Suits | Primary focal hyperhidrosis of the underarms, palms or soles that has not responded to antiperspirants; craniofacial sweating that affects daily life. | Thin, crepey under-eye skin; dull, inflamed or acne-prone skin; post-procedure recovery; people who want quality rather than volume. | Crepey, dehydrated skin of the face, neck and hands; people wanting quality not shape; first-time injectable patients. |
| In one line | If sweating stops you shaking hands, this is one of the few treatments in aesthetics with level I evidence; if it only threatens a blow-dry, that is a different conversation. | The injected courses are a sensible part of a skin plan; the salmon-sperm facial is mostly the microneedling doing the work. | One of the few injectables where 'natural' is built into the design. |
Risks
Injection pain (palms especially), bruising, temporary hand weakness, brow or forehead weakness with scalp or facial dosing, and the cost of repeating it two or three times a year.
In Singapore
Botulinum toxin products are prescription-only medicines in Singapore, prescribed and injected by doctors; axillary hyperhidrosis is a licensed indication and other sites are off-label. They are not advertised to the public, and this page is an editorial review, not an offer.
“If sweating stops you shaking hands, this is one of the few treatments in aesthetics with level I evidence; if it only threatens a blow-dry, that is a different conversation.”
Questions
How long do sweat injections last?
Will I sweat more somewhere else?
Is 'blowtox' worth it?
Cite this review
Aesthetics International (2026). Sweat injections for hyperhidrosis: does it work? Evidence, risks and verdict. https://aesthetics-international.org/treatments/hyperhidrosis-sweat-injections/ (reviewed 1 October 2026).
Editorial, unpaid and independent of any manufacturer. Verdict: Established. See what works and what doesn't across all 153 reviews. Spotted an error or a newer study? Suggest a correction — changes are logged on the corrections page. Terms are defined in the glossary.
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