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Thornit Canker Powder - 20g

Thornit Canker Powder - 20g

Regular price £13.90 GBP
Regular price Sale price £13.90 GBP
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Thornit Canker Powder for dogs, cats and rabbits is still made using Mr W Watchman's proven formula of 1907. Canker is caused by a mite, picked up in grass, often dropped from foxes. The more usual forms are brownish waxy scabs inside the ears. These are made by the mite wishing to chew the ear in the dark. The scabs can be dry, or weep slightly, causing a smell. The other type is much more offensive, and stinks of gangrene, whilst discharging globs of pus. In both cases the symptoms are scratching, head shaking rubbing of ears on the floor, and general distress. There can also be red sores, inflammation and blood clots caused by constant scratching. The standard treatment of drops and antibiotics give only temporary relief. There are NO antibiotics in Thornit, so it can be used in perfect safety.

Key Features

✔ Mr. W. Watchman's proven formula of 1907.

✔ For the treatment of canker (caused by ear mites).

✔ Contains NO antibiotics.

✔ Safe to use.

✔ Easy to apply.

✔ Suitable for dogs, cats and rabbits.

Instructions for Use

Instructions - EARS
Any excess moisture can be gently mopped up with a cotton wool swab. Do not remove wax. Under normal circumstances powder should not be put in ears, but the brown wax acts as a cork.

Get the animal in a good position lying on its side. (with cats this can be difficult, and help may be needed). Apply a pinch of Thornit Canker Powder using the end of a spoon. Lightly dust round the inner ear avoiding the ear hole. Gently massage the powder in with your finger from the outside. Apply Thornit Canker Powder twice a day. Relief comes with the first dose, but the treatment should continue for one to five days (usually three). When the brown wax starts to move - stop. This means that the mite are dead and the wax will come away, pushing out the powder and leaving a clean ear. A pinch of Thornit Canker Powder in each ear once a week will keep the animal free from re-infection.

For breeds with long ears it is advisable to dip the ends of the ears in Thornit Canker Powder once a week.

For Stripping Hair From Ears: Apply ½ teaspoon to the hair - hair comes out easily.


A vet in Australia has isolated the mite that causes intense distress in dogs who are in constant motion, scratching and biting all parts of their body. The vet says the ear mite has transferred itself to the scurf of the body. It is very tiny and mobile. Vets can find nothing wrong. Skin scrapings sent to vet colleges give a clean bill of health. Shampooing is useless. Treatment: Dust Thornit Canker Powder lightly onto the skin. If the animal has long hair, part the hair with a comb feeding a small trickle of Thornit Canker Powder on the exposed skin. A little powder goes a long way.

If the animal drags its bottom on the floor and if it's not anal gland trouble, the mites could have made a breeding bed under the tail. Treatment: Apply a tiny amount of animal skin cream to the finger of a glove and dip into the Thornit Powder. Apply just below the tail where necessary.

Mites can get between the claws, making the animal lick the paw constantly (turning the pads into a lollypop) and then they tear out their fur and finally nibble a hole in themselves. Treatment: Hold the paw in a plastic bag containing a small amount of Thornit Canker Powder. Work the powder between the claws, into the pads and a little way up the leg.

*Please Note: For all treatments only a very small amount of Thornit Canker Powder is needed per dose. Care should be taken as the active ingredient iodoform could stain pale carpets or furnishings.

For external use only and only to be administered as per these instructions. Keep out of reach of children.

Ingredients and nutrition

Composition: Zinc Oxide, Talc, Iodoform, Boric.

Thornit is a powder that is based on Iodoform. At the beginning of the 20th century, iodoform was commonly used in medicine as a healing and antiseptic dressing for wounds and sores. Iodoform has a very distinctive medical smell that helps to discourage the mites (you may recognise the smell from sticking plasters).

Thornit Canker Powder also contains the active ingredient Boric which is an effective antiseptic & insecticide that helps kill off parasites and stops the growth of bacteria. Boric works by breaking down the metabolism of insects. Zinc oxide is added as a drying and curing agent that reduces inflammation and irritation to stop the itch cycle. These chemicals come in crystallised form and are ground down as fine as is possible, though may still be slightly gritty in consistency. They are all added to carrier powder (talc) to make it easier for application.


Size: 20g.
SPR Centre Product Code: THORN665.

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For all orders placed on our website, delivery is available to the UK only.

All orders Monday-Thursday will be processed and Despatched the folowing working day (e.g. orders placed on Monday will be sent Tuesday etc.)

Orders sent Friday-Sunday will be processed and Despatched on the following Monday.

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