Vet Blog

What You Need to Know About Heartworm Treatment

April 19, 2019

While no owner wants to hear a diagnosis of heartworms, the truth is that in the majority of cases, heartworms can be treated.

Of course, much like any other medical condition, the sooner your pet is diagnosed and starts treatment, the less damage there is likely to be to his or her health and the better the prognosis for recovery.

April is heartworm awareness month and our vets in San Antonio, TX are committed to educating all owners about this potentially deadly parasitic infection. Since many owners know very little about what happens in the event that their pet contracts heartworms, here is what you need to know about heartworm treatment.

Restricting Exercise from the Point of Diagnosis Is Essential

Heartworms set up residence in the heart, lungs, and their associated blood vessels. Here they mature into adults and reproduce, their numbers growing and clogging up the blood vessels and organs more and more. This prevents the normal flow of blood around the body which can cause damage to all of your pet's major body systems and other organs including her kidneys and liver.

Physical activity causes your pet's lungs and heart to work harder than usual, and this can speed up the rate at which heartworms cause damage to the heart and lungs. One of the initial symptoms that you may have noticed could have been your pet coughing after little playing or exercise. This could be an indicator of heartworms.

As soon as your pet is diagnosed with heartworms, you must follow your veterinarian's advice regarding exercise restriction. In most cases, this must be restricted immediately and not recommenced until your veterinarian in San Antonio, TX has cleared your pet of heartworms and declared her healthy enough to exercise.

Your Pet May Need to Be Stabilized before Treatment Can Commence

If your pet is believed to have advanced heartworm disease and is severely affected, it may be necessary for your veterinarian to stabilize her before they can treat her. This is especially true if she has a pre-existing medical condition such as high blood pressure. Often, a range of treatments is used to do this, including intravenous fluids and oral medications such as beta-blockers. Your vet will be able to advise you if your pet needs stabilizing first and how long this is likely to take.

Treatment Takes Place over Multiple Appointments

There is an injectable heartworm medication that can kill adult parasites. While it is possible to give an animal a large enough dose to destroy all heartworms at once, this is not advisable. Killing all the heartworms in one go can actually cause your pet's body to go into shock. Instead, there is an approximate treatment timeline that you can expect your vet to adhere to. This is as follows:

  • Orally administered prednisone and doxycycline which can help reduce the likelihood that your pet will experience a bad reaction to the death of the heartworms.
  • A visit as a day patient where your pet is given a heartworm preventative to kill any juvenile heartworms that may be present. This is done as a day patient so that your pet can be closely monitored in case she has a reaction to the treatment or the death of the microfilaria.
  • Heartworm preventatives must continue to be given monthly as normal.
  • The first injection of melarsomine is given to kill adult heartworms. Close monitoring of your pet is essential.
  • Approximately 30 days later a second melarsomine injection to kill adult heartworms is given. Again, your pet must be monitored for adverse reactions.
  • A third melarsomine injection to kill adult heartworms is given a day after the second.

You will then be expected to continue to ensure that your pet is heavily restricted from exercise until checks are carried out to clear your pet of heartworms. These include a test for check for microfilaria (heartworm larvae) around 3-5 months after the third melarsomine injection and a test for adult heartworms and microfilaria which should be carried out 6 months after the final melarsomine injection.

There Can Be Risks of Complications from Treatment

Although every effort will be made to ensure that your pet is treated as safely and effectively as possible, there is some level of risk associated with the treatment of heartworm disease. For this reason, your pet will be closely monitored while she is receiving the melarsomine injections. Some of the side effects and complications that can arise as a result of heartworm treatment include:

  • Soreness and swelling at the injection site
  • Abscess at the injection site
  • Loss of appetite
  • Excessive panting
  • Respiratory distress
  • Persistent vomiting or diarrhea
  • Worsening cough
  • Collapse

If your pet exhibits any of the symptoms listed above, it is crucial that you seek the advice of your veterinarian in San Antonio, TX at Deerfield Animal Hospital as soon as possible.

For more advice and support on heartworm treatment for your pet, don't hesitate to make an appointment at our animal hospital by calling (210) 492-5575 today!

Same-day appointments available!