If your are having trouble getting the Frontline to work, you may have to resort to Program (injection) It lasts 6 months and is about £20
As for the house, I was told the spray only kill fleas and larvae in direct contact, not eggs. The residue will remain effective for about a month, and you need to vaccumm every other day as the vibration prompts the eggs to hatch, then the larvae will die. I found it did take about 2-3 weeks of scrupulous laundry and vaccing especially corners and sofa cushions etc then they wer all gone.
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