Can I use ivomec to kill tapeworms in my cats? If so, what doseage. I give my dogs ivomec once a month for heartworm preventative but have not used it on the cats. The dogs take it orally. Can the cats take it orally too or do I need to inject the ivomec for tapeworm? A: Ivermectin does not kill tapeworms. It is very likely that the worms you are now seeing are tapeworm segments. Your vet can confirm this and prescribe appropriate medications. It is very likely that the worms you are now seeing are tapeworm segments. Ivermectin proved to be even more of a ‘Wonder drug’ in human health, improving the nutrition, general health and wellbeing of billions of people worldwide ever since it was first used to treat Onchocerciasis in humans in 1988. Ivermectin can be used as effective treatment for this condition. Ivermectin is available in many forms including, topical, oral and injectable. Injectable ivermectin may be an option for cats uncooperative with oral or topical treatment, as this drug is highly distasteful. Ivermectin has a very broad “margin of error” or safety margin, which means that very large doses can be and are used without bad effects, except in certain bloodlines of Shelties, Collies, and a few other breeds and crosses who have inherited a certain susceptibility to bad reactions. Ivermectin is a medication used to treat many types of parasite infestations. This includes head lice, scabies, river blindness (onchocerciasis), strongyloidiasis, trichuriasis, and lymphatic filariasis. You may therefore be wondering if ivermectin containing products such as your dog’s Heartgard pill can kill tapeworms. You may also wonder if ivermectin labeled for cattle may kill tapeworms.The answer is no Ivomec and ivermectin products do not kill tapeworms. You need to use the drug praziquantel. You can get this from your vet or occasionally from pet stores. The dosage will be on the box. You need to use the drug praziquantel. Ivermectin is also used in the so-called slow-kill or soft-kill method of heartworm treatment — although this is a bit of a misnomer. Ivermectin does not directly kill adult heartworms, but it does kill the microfilaria (larval form) of the heartworm. Unfortunately, Ivermectin does not work against tapeworms, but the drug's method of action allows it to eliminate most intestinal worms, as well as external parasites like scabies and lice.