ive used this from this place derbyshire fox rescue and it works well just takes a long time as you add a few drops into the dogs food untill the there,s none left and that takes about 5 weeks , i now use ivomec super its 1ml to 50 kg it works the same as ivomec but lads make sure you read the dosage i give 0,4 to the terriers and 1ml to the lurcher and it works well ,but doe,s dont cover tape worm .my dogs pick mange up every season from an area i work my dogs and every year about half way through season they all start showing signs so a quick jab with this stuff and its cleared up in no time