From felinecrf.org....
Slippery Elm Bark Formulations
Loose Powder
Ideally, you want organic or wild-crafted slippery elm bark powder from most good health food shops. See
below for sources.
Capsules
If you cannot find loose slippery elm bark, you can usually find capsules in a 350-400mg size. Try to ensure the capsules contain only pure slippery elm bark, no fillers, because it can be virtually impossible to make the
syrup recipe from capsules containing anything other than slippery elm bark (it will not thicken).
Unfortunately it is difficult to find capsules that don't contain magnesium stearate because it is a glidant used in the manufacturing process (it helps the powder flow when the capsules are being filled). Magnesium stearate is safe for cats but may affect the thickening of the syrup, though some people have been able to make it successfully from such capsules. There is one US supplier
below selling capsules containing slippery elm bark only.
Tinctures
I would avoid tinctures because they often contain other ingredients, especially alcohol, though some members of my support group in the USA have managed to find one brand without alcohol.
Slippery Elm Bark Dosage
The usual dosage is:
- 1/8 to 1/4 (0.125 - 0.25) of a teaspoon of the organic or wild-crafted slippery elm bark powder once or twice a day; or
- one 350-400mg capsule a day. You can give these whole or open them and sprinkle on the cat's food once or twice a day.
Most cats are given slippery elm bark daily, but some cats do not need it every day, so experiment and see what works best for your cat.
I open the capsules and sprinkle the slippery elm bark into my cat's food and mix it up, but slippery elm bark has a bittersweet flavour which some cats do not like. In that case, try giving it in a capsule, either the one it came in (though these may well be too big for the average cat) or, if you are using loose slippery elm bark, purchase
gelcaps separately for this purpose.
Some people have found their cat will eat slippery elm bark if it is mixed in a little
baby food (make sure the baby food does not contain any onion).
Syrup Recipe
You can also make slippery elm bark into a syrup that is used for digestive problems or for mouth sores or ulcers. It has the same soothing and healing effects in the mouth — try dabbing in your cat's mouth ulcers if required. The syrup is weaker than the straight powder, so you can give a little more of it. Some people have told me they find it hard to place the syrup on their cat's mouth ulcers if they are in hard-to-reach areas of the mouth. In such cases, you may wish to use a syringe to aim the syrup at the ulcers.
If you are using slippery elm bark decanted from capsules, you need pure slippery elm bark with no fillers, otherwise the syrup will usually not thicken properly.
Stovetop Method
- Take a stainless steel or heat-proof glass pan (not an aluminium or non-stick one).
- Put one cup of cold water in the pan.
- Sprinkle 1 to 1.5 tsp of slippery elm bark powder on to the water.
- Let it sit until the powder is damp (this should not take too long), then bring to the boil stirring constantly.
- Reduce the heat and simmer, still stirring constantly, until it thickens, about 3 minutes or so. It will be the consistency of watery egg whites.
- Allow to cool and give ¼ - ½ (0.25 to 0.5) teaspoon up to 4 times a day.
- This will keep at room temperature for a day or in the fridge for up to five days.
Microwave Method
For the non-cooks among us, one of my support group members came up with this method but it may not work with powdered slippery elm bark.
- Take a glass container which holds two cups.
- Put one cup of water in the cup.
- Add 1 to 1.5 tsp of slippery elm bark powder.
- Heat in the microwave on high for about 1.5 minutes.
- Remove from the microwave and stir, then put it back in for about another 30 seconds.
- Keep an eye on it because you do not want it to boil over.
- Remove from the microwave and stir again.
- Allow to cool and give ¼ - ½ (0.25 to 0.5) teaspoon up to 4 times a day.
- This will keep at room temperature for a day or in the fridge for up to five days.
Slippery Elm Bark: Where to Buy
USA
San Francisco Herb Co sells loose slippery elm bark powder at the best price I've found, US$22.20 per pound plus exact shipping cost, but their minimum order is for US$30. They will waive this on request and charge a US$7 small order fee instead; alternatively you could stock up on other products such as catnip.
Frontier Natural Products Co-Op sells loose slippery elm bark, in both organic and standard forms. You can also find Frontier products on
Amazon.
Mountain Rose Herbs sell 4 oz of slippery elm bark powder for US$9.75.
Whole Foods Market sells slippery elm bark in bulk in its stores in USA and Canada.
Vitacost sells 4 oz of the NOW brand for US$9.00.
Iherb sells 4 oz of the NOW brand of slippery elm bark powder for US$8.99.
Iherb also sells 100 Christopher's Original Formula 400mg capsules without any fillers.
Vitamin Shoppe sells slippery elm bark capsules.
Swanson Vitamins sells its own brand 400mg slippery elm bark capsules for US$3.49 for 60.
Canada
Amazon Canada sells a 1 lb bag of Starwest Botanicals organic slippery elm bark powder for CAN$59.99.
Slippery Elm Bark: Cautions
PennState Hershey states that slippery elm bark can inhibit the absorption of other medications or supplements. It is therefore best to give it 1-2 hours before or after any other medications (especially antibiotics), and ideally on an empty stomach, although it is safe to sprinkle it on food if you wish.
Slippery elm bark also contains calcium, so it is probably safer not to use it if your cat has
hypercalcaemia.
Again, don't beat yourself up. 
You did catch the problem.
It's about $4 a pill in Canada, do phone around as I've seen it as high as $5. Zofran, the brand, is ridiculously expensive.
