Another reason some choose to add diatomaceous earth to the food of their mammalian pets and even themselves is because it clears gastrointestinal obstruction by tapeworm. While it does make the gut into parasite ground zero, that is no garuanteed that it will kill all. It will just clear the obstruction.
Wormers are still advisable because the nastier fucks don't stay in the gut for long.
Heartworm, fluke, pinworms. Ever known someone with a hydatid cyst?
I say known because you may not know them anymore. A timebomb.
If you can use a natural remedy as a supplement or tool then go for it, so long as you know the mechanism by which it works first (I give a dirty look here to people I've met in the flesh who advocate black salve for melanoma instead of visiting a clinic). Borax powder in your carpet will destroy flea eggs and cease the reoccurence of oubreaks. Powdered talcum powder and aspartame will offer a one -two punch to ants in your cupboard. I'm not going to tell you how they work because I encourage you to do the research and familiarise yourself whenever possible rather than relying on internet anecdotes.
Humidity sinks such as silica gel products or dehumidifies *may* also contribute towards solving your spider problems in a friendly way that will encourage spiderbro to leave unharmed and find a more appreciative with which to live in symbiosis. 1983's disturbed air comment is very, very interesting. Dehumidifying methods are very good for mold, though which is something you should be far more concerned about than sharing your home with invertebrates.
I recommend that before all else is said and done, you identify and research the creatures in your home other than yourself.
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