is it safe? as long as you don't overuse it or allow the kitty to inhale the dust yes it is. efficacy of it is (seemingly) so-so, at least based on my use of it with my colony.
i put it in my cats food daily and still have seen tapeworm as well as roundworm in the fur near their anus. however, the 2 of them that i have seen with the worms are very skilled hunters - within a hour of eating their breakfast today one of them had caught a small mouse and the other came dashing up to me and proceeded to drop a large mole out of his mouth - so, at least with these 2 it is an extreme scenario.
to treat them with dewormers would be a never ending battle, not to mention my concern about the toxicity with frequent usage. what i might try to do this year is continue to use the d.e. every day and once or twice give them doses of dontral, at least to the 2 "killers".
remember though, d.e. is not fast acting. so it may be a good idea to see if you can get your vet to give you some dontral or you could also buy some panacur-c which is available w/o a prescription.
i think that giving diatamacious earth for coughing is a far stretch. coughing could be caused by all types of things, the best thing would to get diagnosis from a vet before you choose how to treat it.
Isn't diatomaceous earth used to spread along the edges of walls/floors so that bugs walk on it and it gets into their skeletons and dries them out? I thought I heard that as a remedy for some bugs once.
What would be the purpose of adding it to a cats' diet? Just curious.
If you add it to the cat food, make sure it is food grade. And it is hazzardous to inhale.
Yes, it is used as a "natural" treatment for bugs, especially fleas.
The idea behind feeding it to pets is the sharp edges of the pieces of DE are supposed to kill worms.
While a cough can be a sign of worms, it is usually a severe infestation at that point. DE is not going to work quickly enough to help your cat. The cough can be a sign of many things and a vet should be consulted for treatment. You don't want to be treating for worms when it is really a heart issue, for example.