Magnoplasm 100g

Magnoplasm is the traditional drawing paste: dried magnesium sulfate 48% w/w and glycerol 44% w/w in a 100g jar, used as an initial treatment for boils, carbuncles and whitlows. It is not scheduled, so no prescription is needed. Pharmacies have kept it behind the counter for generations, and it is still a first aid room staple for the same reason it always was.

How does Magnoplasm work?

It works by osmosis rather than by any drug action. Magnesium sulfate in this concentration is strongly hypertonic, meaning the paste holds far more dissolved salt than the fluid in the swollen tissue underneath. Water moves from where it is more dilute to where it is more concentrated, so held against inflamed skin under a dressing, the paste draws fluid outward. The glycerol keeps the mix spreadable and stops it drying into a crust on the skin.

That is the whole mechanism, and it explains the two things people find surprising about it. It is not an antibiotic and it does not kill bacteria, so it is not a treatment for an infection that is spreading. And it has to stay in contact under a dressing to do anything at all, which is why smearing it on and leaving it open to the air achieves very little.

How to use Magnoplasm on a boil

1. Spread about 5mm thick on a non-adhesive dressing. Thicker than feels necessary is the usual mistake people avoid; a thin smear dries out and stops working.
2. Apply to the inflamed area, paste side down, then bandage it in place so it stays in contact.
3. Change after 12 to 24 hours. Replace with a fresh dressing if it is still needed.

It may be used cold, but it can be gently warmed to make it easier to spread. Keep it gentle: this is a jar of paste, not something to heat aggressively. For external use only, and store it below 25 degrees.

How long does Magnoplasm take to work?

The dressing cycle on the pack is the practical answer: 12 to 24 hours per application, repeated as needed. A simple boil that is going to respond usually shows some change over the first day or two of consistent use under a dressing. If several days of proper application have made no difference, or things are getting worse rather than better, that is the point to stop and see a pharmacist or doctor rather than keep going.

Magnoplasm for splinters and thorns

This is the other job the paste has always been used for at home. The same osmotic pull that draws fluid from inflamed tissue will soften the skin around a shallow splinter or thorn and help lift it toward the surface, applied under a dressing and left overnight. It works best on the small, shallow, awkward ones you cannot get a grip on with tweezers.

Two honest caveats. Deep splinters, anything under a nail, glass, and anything that has been in the skin long enough to become red and angry are not do-it-yourself jobs, and glass in particular needs proper assessment because fragments do not always come out the way they went in. And the manufacturer makes a dedicated splinter product, Splintex, which is a separate item we do not stock, so we are not going to pretend this is the same thing.

What Magnoplasm is not for

• Open wounds and broken skin. The labelled uses are boils, carbuncles and whitlows, and it is for external use on intact skin. If the skin is already open, ask a pharmacist or doctor what belongs on it rather than reaching for a drawing paste.
• Pimples and acne. A boil and a pimple are different things. Ordinary acne is a skin condition with its own treatments, and a hypertonic paste under a bandage is neither practical nor intended for it.
• Cysts. A sebaceous or epidermoid cyst is an enclosed sac under the skin, not a collection of fluid the paste can pull through the surface. Those are a GP conversation.
• Pets. People do ask about using it on dogs. Ask a vet. Animals lick dressings, body weights differ, and a vet can tell you in a minute whether it is appropriate.

Magnoplasm specifications

Stock the treatment room with more first aid room equipment, or browse the wider first aid supplies range.

Sources. Composition, directions and storage are from the Australian pack copy as published by TerryWhite Chemmart. Indications and Australian scheduling are from healthdirect.gov.au. Last reviewed 17 September 2026.

Always read the label and use only as directed. For external use only. If symptoms persist, worsen, or you develop a fever or spreading redness, see your doctor. This information is a general guide and is not medical advice. For poisoning advice, call your national poisons information service.