Resistance to meds may be a myth

Resistance of Strongyloides worms to anthelmintics

So far there are no reports on resistance of Strongyloides species of dogs and cats to anthelmintics.

This means that if an anthelmintic fails to achieve the expected efficacy, chance is very high that it was not due to resistance but to incorrect use, or the product was unsuited for the control of these parasites. Incorrect use is the most frequent cause of failure of antiparasitic drugs.
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