Topical aluminum chloride is a potent antiperspirant and astringent used primarily to treat excessive sweating/hyperhidrosis of the underarms, hands, feet, and scalp. (Drysol).
It works by reacting with sweat to form a temporary “plug” in the sweat gland ducts.
Topical aluminum chloride is a first-line treatment for primary focal hyperhidrosis, working by forming plugs in eccrine sweat ducts through a chemical reaction with intraductal keratin.
Aluminum chloride works by reflux entrance into the terminal intraepidermal eccrine duct, combining with intraductal keratin to produce fibrillar contraction and functional ductal closure.
This altered keratin is shed weeks later, with consequent return of ductal patency and sweating, explaining why continued application is necessary.
It prevents moisture from reaching the skin’s surface.
It is the first-line therapy for severe sweating that doesn’t respond to regular antiperspirants
It is most commonly used for axillary, palmar, and plantar hyperhidrosis, with concentrations typically ranging from 12.5% to 30% in various formulations.
Studies demonstrate significant sweat reduction across multiple body sites.
Frey’s Syndrome: Helps manage facial sweating triggered by eating.
Blister Prevention: Used by hikers and military recruits to prevent foot blisters during long walks in heat.
It acts as an astringent to stop minor bleeding after procedures like skin biopsies.
Aluminum chloride is available in various concentrations, with “hexahydrate” being the more potent form typically found in prescription products.
Over-the-Counter (OTC): Usually contains 12% to 15% aluminum chloride.
Common Brands: Certain Dri (12%), SweatBlock (14%), and clinical-strength options from brands like Secret or Gillette.
Prescription-Strength: Typically 20% or higher (up to 35% for hands and feet).
Common Brands: Drysol, Xerac AC, and Hypercare.
Application at bedtime:sweat glands are least active at night, allowing the plug to form most effectively.
Ensure the area is completely dry and using a hairdryer on a cool/warm setting can help.
Applying to damp skin creates hydrochloric acid, which causes severe irritation.
Avoid Shaving: Wait 24 to 48 hours after shaving before applying.
Wash off in the Morning: Thoroughly clean the area with soap and water to remove residual medication.
Frequency: Use nightly for 1–2 weeks until sweating is controlled, then reduce to 1–2 times per week for maintenance.
Side Effects & Cautions
Skin Irritation: Itching, burning, stinging, or redness are common, especially with higher concentrations.
Applying 1% hydrocortisone cream the following morning can help soothe irritation.
The chemical can stain or weaken fabrics like cotton and can harm certain metals.
Wear an old T-shirt or use a covering at night.
With kidney disease, a small amount of aluminum may be absorbed systemically.
For axillary hyperhidrosis, 20% aluminum chloride hexahydrate achieves response rates of 33-72% depending on severity.
In palmar hyperhidrosis, 20% aluminum chloride hexahydrate produces significant reduction in skin water vapor loss within 1-2 weeks, though effects disappear within 48 hours of stopping treatment.
For plantar hyperhidrosis, both 12.5% and 30% concentrations are effective, with 12.5% recommended for outpatient treatment due to comparable efficacy and better tolerability.
Proper application: apply to dry, clean skin during sleep or prolonged non-sweating periods.
Initial regimens typically involve nightly application for 1-2 weeks, then reduced frequency (2-3 times weekly) for maintenance.
Occlusion with plastic wrap for 6-8 hours can enhance efficacy but is not always necessary.
Its primary limitation is local skin irritation, including itching, burning, and contact dermatitis, occurring in approximately 5-30% of patients.
Irritation is often transient and may resolve with continued use, though some patients require discontinuation.
Newer formulations with aluminum lactate or sesquichlorohydrate show comparable efficacy with improved tolerability profiles.
Aluminum chloride has been used successfully for diabetic gustatory hyperhidrosis/facial sweating triggered by eating, and craniofacial hyperhidrosis when combined with systemic agents like clonidine.