Heartworm disease
is a very serious and fatal disease in dogs and cats. It is one of the most
common causes of death in dogs in the South. Heartworms are carried by the
mosquito. When an
infected mosquito bites a dog, it can inject immature heartworms into the
blood stream of the dog.
These immature worms eventually find their way to the heart where they mature
into adult worms.
When there are worms in the heart, the heart can not function correctly. The
worms disrupt the flow
of blood through the heart and to the lungs, and they also damage the muscles
of the heart. The
worms present in the heart can continue to mate and create more worms. The
baby worms stay in
the blood stream until they become adults. The adults then move to the heart.
Untreated, heartworm
disease will lead to congestive heart failure and death. Indoor cats and
dogs are not immune
from developing heartworm disease. Mosquitoes can enter our homes, and
the dogs must go
outside to urinate and defecate.
Heartworm disease is very easy to
prevent. It is much better to prevent the disease than to end
up having to treat the disease. Treatment does have some risks
associated with it and can be very
costly. There is no treatment for heartworm disease in cats. All dogs and cats
should be put on
heartworm preventative as early as three months of age. Heartworm prevention
must be given to the
animal the rest of its life. There are several brands of heartworm
preventative available.
Testing for Heartworms
Dogs and cats 6 months and older should be tested for heartworms prior to
beginning heartworm prevention. The growth period of the heartworm is
approximately 5-6 months. This means that if the dog were to be exposed to
heartworms at a very early age, the disease should show positive by six months
of age. There are many veterinarians who believe that it is not necessary to
test a dog that is younger than 1 year of age, because it is most likely they
are negative. I do agree that it is very rare to find a dog less than one year
of age that is positive for heartworms. However, I have had a 9 month old dog
test positive for heartworms. I prefer not to take any chances. Some heartworm
preventatives can actually be harmful if given to a dog that does have
heartworms. Testing a dog prior to putting him/her on preventative is
important for many reasons. If you place a dog on preventative without first
testing it and then later down the road it is discovered that the dog is
positive for heartworms, there could be several possibilities why. One, the
dog could have had heartworms prior to starting prevention. Two, the product
may have failed. Three, the owner may not have been compliant and may have
forgotten to give the preventative. If the dog is tested prior to giving
preventative, we can at least determine in this scenario that the dog was not
positive prior to starting prevention. Also, as mentioned previously, some
heartworm preventatives can be harmful if given to a positive dog. Dogs
and cats
should be tested every year for heartworms regardless if they have been given
heartworm preventative. Like vaccines, no heartworm prevention can be
100% effective for every dog. It is also very easy for some owners to forget
to give the preventative on a regular basis. A lapse in giving preventative
can lead to infection. Also, some dogs are very clever and will take the
heartworm tablet and spit it out without the owner knowing. Testing a
dog or cat every year for heartworms in not a way for veterinarians to make more
money. It is to ensure that your dog or cat does indeed stay heartworm negative.
Heartworm Preventatives
Heartgard
Heartgard is a chewable tablet that can be given to dogs as young as three
months of age. Heartgard must be given once a month. This drug kills any baby
worms that may be in the blood stream, thus preventing them from growing to
adults. Heartgard does not kill adult worms. Heartgard also kills and prevents
the intestinal parasites, roundworms and hookworms. This preventative is also
made for cats.
Iverhart Max
Iverhart Max is the generic form of Heartgard Plus with an added ingredient
that kills and prevents tapeworms. No other heartworm prevention is labeled
for the treatment and prevention of tapeworms. Iverhart Max cost less than
Heartguard Plus. It comes in a flavored tablet. This preventative is not
made for cats.
Interceptor
Interceptor is a non-chewable tablet that must be given every month to prevent
heartworms. It, too, can be given as early as three months of age. It works in
the same manner as Heartgard. Interceptor also helps kill and prevent
roundworms, hookworms, and whipworms. It does not kill adult worms. The
difference between Interceptor and Heartgard is that Interceptor is affective
against whip worms, Heartgard is not. This preventative is also made for cats.
This preventative should not be given to heartworm positive dogs or cats.
Sentinel
Sentinel is also a non-chewable tablet that must be given once a month. It
prevents heartworms, roundworms, hookworms, whip worms, and helps control
fleas. It does not kill adult heartworms. Sentinel does not kill adult fleas.
It only sterilizes them so that they can not produce more fleas. You may still
see adult fleas on your dog. This heartworm prevention is not
made for cats.
Revolution
Revolution is a topical medication that prevents heartworms, roundworms,
hookworms, earmites, mange, and fleas. It is available for both cats and
dogs.