Medication

Drysol (Aluminum Chloride 20%)

Drysol is prescription-strength aluminum chloride, the cheapest thing that genuinely works for hyperhidrosis. It also stings and irritates, which is why people abandon it. Almost all of that is fixable: apply it to completely dry skin at night, and wash it off in the morning.

At a Glance

Drysol is a 20% aluminum chloride hexahydrate solution in alcohol — an antiperspirant several times stronger than anything on a drugstore shelf. It is the first rung on the treatment ladder for excessive sweating of the underarms, palms, and soles, and for many people with mild to moderate hyperhidrosis it is enough. It costs a few tens of dollars and a bottle lasts months. The catch is irritation: stinging, redness, and itch are common, and they are mostly a consequence of applying it wrong.

Key Facts

AKA	Aluminum chloride hexahydrate 20%, Xerac AC (6.25%), Hypercare
Drug Class	Topical antiperspirant (metal salt)
Rx or OTC	Prescription in the US; weaker aluminum chloride antiperspirants (around 12%) are sold over the counter
Typical Strength	20% solution, applied at bedtime
Time to Work	Often within a week; full effect in 2–4 weeks
Evidence Level	Good. Long-established and genuinely effective for mild to moderate hyperhidrosis.
Important	Apply only to completely dry skin. Applying to damp skin is what causes the burning.

How It Works

−

Aluminum salts do not switch off the sweat gland. They block the exit.

When aluminum chloride meets the moisture inside a sweat duct, it forms a gel-like plug of aluminum hydroxide near the surface of the duct. Sweat cannot get past it. Over repeated nightly applications, the plugs build up and the ducts stay blocked. There is also evidence that longer use causes some shrinkage of the gland itself, though the plug is the main event.

Two things follow from this. First, it works better on skin that is not already wet — a duct full of sweat dilutes the solution and drives the reaction in the wrong place, which is exactly what produces the sting. Second, the plugs wash out over days, which is why this is a maintenance treatment rather than a course.

The 20% prescription strength is roughly double the strongest over-the-counter aluminum chloride products, and several times the concentration of an ordinary aluminum-based antiperspirant.

What It Treats

−

Hyperhidrosis

Strong evidence

A higher concentration of aluminium chloride hexahydrate, plugging the top of the sweat gland more effectively. Irritation is the main reason people stop.

Who It's For & Who It's Not

Who it's for

Anyone with excessive underarm, palm, or sole sweating who has not yet tried a proper prescription-strength antiperspirant. This should be the first thing tried, before anything expensive.

People who want a treatment with no systemic effects at all — nothing is absorbed in any meaningful amount, so there is no dry mouth, no blurred vision, no interaction with anything.

People who need something they can stop and restart freely, or use only in summer.

Who it's not for

Anyone with broken, raw, freshly shaved, or already irritated skin. Wait until it has healed.

People with severe hyperhidrosis that soaks through clothing daily — Drysol is usually not enough on its own, though it is still worth combining with other treatments.

People with facial or scalp sweating. It is too irritating for the face, and there are better options.

Anyone who tried it, got a chemical burn, and was never told about the dry-skin rule. That is a reason to try again properly, not a reason to give up.

How to Take It

How to apply it — the part that decides whether it works

Apply to completely dry skin. Not towel-dry. Bone dry. If you have just showered, wait. Many people use a hairdryer on cool for a minute first. This is the single most important instruction on the page: aluminum chloride reacting with water on the skin surface produces hydrochloric acid, and that is the burning people describe.
Apply at night, before bed. Sweat production is at its lowest overnight, so the solution can get into the ducts and form its plugs undisturbed. Applying it in the morning wastes it and irritates more.
Wash it off in the morning. Plain water and a gentle cleanser. The plugs have already formed; leaving the solution on all day only irritates. Then use your normal antiperspirant or deodorant if you want.
Use a small amount. A thin film over the affected area. More does not work better; it just burns.
Do not use it right after shaving. Leave at least 24 hours, ideally 48.
Let it dry fully before dressing. Aluminum chloride can damage fabric and jewelry.

How often

Every night for the first week or so, until sweating is controlled. Then drop back to whatever maintains it — for most people that ends up being once or twice a week, sometimes less. Overusing it once it is working is the main cause of ongoing irritation.

Palms and soles

These need more persistence than underarms; the skin is thicker and the response is slower. Some clinicians suggest covering the area overnight with a thin plastic film or gloves to increase penetration. It does work better — and it irritates considerably more, so it is worth discussing with your dermatologist first rather than improvising.

What to Avoid

−

There are no drug interactions and no systemic concerns. Nothing meaningful is absorbed. The frequently repeated worry linking underarm antiperspirants to breast cancer or Alzheimer's disease has been looked at repeatedly and is not supported.

Damp skin

Repeating it because it is the whole game.

Freshly shaved skin

Shaving creates hundreds of microscopic breaks. Aluminum chloride on top of that stings badly and can leave a genuine chemical burn.

Broken, cracked, or inflamed skin

, including active eczema or a rash in the fold.

Eyes and mucous membranes

It hurts. Rinse thoroughly with water if it happens.

Good clothing, silver, and jewelry

Aluminum chloride solutions can stain and can corrode metal. Let the skin dry fully first.

Leaving it on all day

Wash it off in the morning.

Combining it with a retinoid or acid on the same skin

— for instance if you are treating razor bumps in the same area. Space them out or alternate nights.

Side Effects

Every side effect of this drug is local. There are no systemic ones.

Common and expected

Stinging or burning on application. Very common, and usually a sign the skin was not dry enough or the area was recently shaved.
Redness and itching in the treated area.
Dryness and flaking.
Irritant dermatitis if it is used too often or left on too long — a red, sore, sometimes weeping patch.
Damage to clothing, and tarnishing of jewelry.

Tell your doctor

Irritation that persists despite applying to dry skin, washing it off in the morning, and reducing the frequency. There are gentler strengths, and there are other rungs on the ladder.
A rash that spreads beyond where you applied it, or that blisters. Allergic contact dermatitis to aluminum chloride is uncommon but it happens.
Compensatory sweating elsewhere. Rare with topical treatment, but worth mentioning.

Stop and get care

Skin that is genuinely burned — blistered, weeping, or eroded. Stop using it, treat it as a burn, and get it looked at rather than pushing through.

How Long Until It Works

−

Faster than most hyperhidrosis treatments. Many people notice a difference within the first three to five nights, and the full effect arrives at two to four weeks with nightly use.

Palms and soles are slower and less predictable than underarms — give those four to six weeks before deciding.

Once it works, the goal is to find the lowest frequency that keeps it working. Most people settle at once or twice a week.

What Happens When You Stop

−

The plugs wash out and sweating returns to baseline over about a week. There is no rebound and no withdrawal — you simply go back to where you started.

Nothing is lost by stopping for the winter and restarting in spring, which is what a lot of people do.

Who should not take it+

Do not use Drysol on:

Broken, raw, or freshly shaved skin Skin with active eczema, a rash, or a healing wound The face, eyelids, or genital skin Skin you are also treating with a retinoid or an acid, on the same night

Stop and speak to your dermatologist if you develop a spreading or blistering rash, which could indicate an allergy rather than simple irritation.

FAQ+

Why does it burn, and how do I stop it?Because aluminum chloride reacts with water. Applied to damp skin, it produces hydrochloric acid right at the surface, which is exactly the sensation people describe. The fix is genuinely dry skin — wait after showering, or use a cool hairdryer — plus applying at night, washing it off in the morning, and not using it within a day or two of shaving. Most people who "cannot tolerate Drysol" were never told any of this.

Can I just use a strong drugstore antiperspirant instead?Try it first, honestly. Over-the-counter aluminum chloride products at around 12% help a lot of people with mild sweating and cost less. Drysol is the step up when those are not enough.

Does it work on hands and feet?Yes, but less reliably and more slowly than on underarms, and irritation is more of a problem. If four to six weeks of nightly use is not enough, iontophoresis is the usual next step for palms and soles and it works well.

Do I have to use it every night forever?No. Nightly to get control, then as little as once or twice a week to maintain it. Using it more often than you need is the main cause of irritation.

Is it safe? I have read things about aluminum.It is safe. Essentially nothing is absorbed through intact skin in a meaningful amount, and the claims linking antiperspirant aluminum to breast cancer or Alzheimer's disease have been investigated repeatedly without support. The real risk of this product is a sore armpit.

What if it is not enough?There is a clear ladder. Next come the prescription topical anticholinergic wipes and gels — Qbrexza and Sofdra — then iontophoresis for hands and feet, then Botox injections for underarms, then oral anticholinergics like glycopyrrolate or oxybutynin, and finally miraDry for a permanent reduction in underarm sweating. Each step costs more or carries more side effects than the last, which is why starting at the bottom is sensible.

Can I use deodorant as well?Yes. Wash the Drysol off in the morning, then use whatever deodorant or ordinary antiperspirant you like. They do different jobs — deodorant handles smell, Drysol handles sweat.

Will it stain my clothes?It can, and it can tarnish jewelry. Let your skin dry completely before dressing.

Can I use it while pregnant or breastfeeding?It is topical and essentially not absorbed, so it is generally considered a reasonable option. Confirm with your obstetrician if you want to be certain.

Does it help facial or scalp sweating?Not really — it is too irritating for facial skin. Facial and scalp sweating is usually managed with oral glycopyrrolate, topical glycopyrronium used carefully off-label, or Botox.