fleas can develop an imunity to teh flea medication, so what you might want to try doing is change youre spot on meds every month or coupel of months.... as far as the infestation, the fleas that she had before layed eggs and now the eggs are hatching..... you need to clean the floor or carpet really good, im not rally fond of the sprays either, but so far we are keeping fleas under control by vacuming a lot, and also using flea shampoo twice a week (i tried the spot ons, but some of them are expensive and they didnt seem to work for me either...... the system i have now with flea shampoo and vacuming seems to work though.... oh and the flea shampoo makes him smell good too
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