4. Make your own mixture
One key maggot killer is permethrin, which can be found in spray form or you can make your own.
Simply mix four parts boiling water with one part permethrin dog shampoo.
Then slowly pour the mixture over any maggots.
One caveat is to make sure you wear gloves when using permethrin, as getting it in the eyes, ears, nose, or mouth can cause irritation.
Permethrin can also be fatal to cats and fish, so maybe opt for another method if you have pets.