I use a natural remedie which I get from my vet's , it containes Tincture
of picrasma excelsa, grapeseed oil, neem oil, Essential oils of lemon,
orange, grapefruit, cedarwood, eucalyptus, citronella, lavender and sage.
 
3 to 5 drops put on the back of the animals neck and used once a week
helps keep the dreaded flea at bay.
[Posted in FML issue 4239]