I used my last doses of Heartguard on my two 58 & 63 lb Weimaraners. I called my vet and was told I have to have the heartworm test before I can get any more. Which to me is just a waste of money, so now I am looking elsewhere. I came across this site that sells a Generic version of Heartguard at 1/2 the price I am paying for the brand name. Shipping is $5 or they have other discounts if you are a frequent buyer. http://www.petcarechoice.com/index....play/pn/Nuheart.Heartworm/product_id/9324.htm Does anyone here use it? Or is there something else I can use?