We might have -finally- found a grooming powder suitable for use on the shelter cats, and is easy to procure: this product is from iHerb. Actually meant for babies, but ingredients are safe and even include extracts like echinacea and goldenseal. There are no artificial ingredients at all. Very hypoallergenic.
Costs S$9.27 before discounts and delivery charge.
Grooming powder is not only useful for combing out matts for a longhaired cat. After we bathe cats, some are not able to stay still to the end of the blowdrying session. Other wouldn't even let the hairdryer near them. For kittens we wet wipe daily because they are dirtier, powdering them after makes them stay dry.
[It is also a protip to powder white paws and other areas before a photoshoot.]
Buy the powder fr om iherb.com, and if you are a first time iherb customer, use our code AVA985 to get US$5-10 off your first purchase. This also gives us credits we can use to offset the supplements we buy from iherb for the sick cats.