ADOPCIONES: 941-747-8808 ext. 313

Heartworm Disease

heartworm graphic

hsmc-full-of-loveIs Your Dog at Risk?

Heartworm disease is a serious and potentially fatal disease primarily affecting dogs, and it is most prevalent in moist, humid regions along the Atlantic and Gulf coasts. Canine heartworms (Dirofilaria immitis) are potentially fatal parasites that infest the cardiovascular and respiratory systems of dogs. Heartworm infections have been reported in all 50 states and, on average, one in 80 dogs become infected.

Heartworm is spread by mosquitoes. When they bite an animal infected by heartworm, they take a blood meal containing microscopic baby heartworms called microfilaria, which then develop into “infective stage” larva over a period of 10 to 14 days. Then, when this infected mosquito bites another dog, the larva enters the new dog host through the mosquito’s bite wound. In the early stages of heartworm disease, dogs show little signs of infection. The longer the infection remains untreated, however, symptoms begin to appear, which can include:

A mild, persistent cough • Fatigue • Decreased appetite • Weight loss

Heartworm disease is a serious, progressive disease, and early detection betters your dog’s chances of responding well to treatment and a full recovery. The fact that there are few—if any—early signs that a dog has been infected with heartworm disease is why regular heartworm testing at your veterinarian’s office is the responsible thing for every pet owner to do. The test requires just a small blood sample from your dog and works by detecting the presence of heartworm proteins. Heartworm testing is simple and quick and should be done twice a year during your dog’s routine visits for preventative care. The cost of heartworm treatment can be significant, which is why every pet owner needs to discuss heartworm prevention with their veterinarian.heartworm

Heartworm prevention medication can be purchased through your veterinarian or by prescription through a pet pharmacy. Two common preventatives are Tri-Heart Plus and Heartgard Plus, which are chewable tablets that are administered monthly.  An injectable preventative called Pro Heart12 is also available. Humane Society of Manatee County Veterinary Clinic, located at 2415 14th Street W. in Bradenton, offers low-to-moderate cost heartworm treatment, and a heartworm test is priced at only $15.00.

Heartworm prevention is simple, effective, and low cost. Call today at 941-747-8808 Option #1 or email clinic@humanemanatee.org to make an appointment for your dog’s basic exam and heartworm test.

You can purchase your heartworm preventative medications at our clinic pharmacy following your dog’s appointment and once your dog is a clinic client, you can purchase the meds online by clicking here and get FREE delivery.


Heartworm Prevention

Please note these medications are prescription products and require that your dog be a patient of the Humane Society of Manatee County to purchase from us.

Tri-Heart Plus Blue < 25 lbs. Rx $22.00, Tri-Heart Plus Green 26 – 50 lbs. Rx $26.00, Tri-Heart Plus Brown 51 – 100 lbs. Rx $30.00

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Heartgard Plus Blue < 25 lbs. Rx $43.00, Heartgard Plus Green 26 – 50 lbs. Rx $48.00, Heartgard Plus Brown 51 – 100 lbs. Rx $54.00

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* Pro Heart* Rx 6 months injection*

Pro Heart*  Pro Heart* Rx 0-25 lbs. $51.00, Pro Heart* Rx 26-50 lbs. $83.00, Pro Heart* Rx 51-75 lbs. $112.00, Pro Heart* Rx 76-100 lbs. $143.00, 101-125 lbs. $174.00

Prices are subject to change without notice.

Heartworm Treatment

Appointments can be made by calling 941-747-8808, Option #1 or by sending an email to clinic@humanemanatee.org.

Heartworm treatment includes the following:

  • Three Immiticide injections*
  • Dexamethasone (anti-inflammatory)
  • Diphenhydramine injection (Benadryl)
  • Bloodwork
  • Methocarbamol (muscle relaxant)
  • Tri-Heart Plus / Heartgard / Pro Heart (injection) (6 – month supply)
  • Heartworm Test

*Three injections – one injection, followed at least one month later by two injections given 24 hours apart; alternative plan used for dogs with a higher worm burden and/or clinical signs; kills about 98 percent of worms.

The three-injection protocol is the treatment of choice of the American Heartworm Society, and therefore we only use this protocol at the Humane Society of Manatee County Veterinary Clinic. This protocol initially kills fewer worms at the beginning of treatment which reduces the impact of the worm emboli (worm fragments) on diseased lungs and lung vessels.

Dogs are given a total of three injections to treat heartworm disease. Your dog will also be placed on doxycycline (an antibiotic) and prednisone (steroid) to help with treatment. Your dog may be sore in the lower back where the injection was given. Adult heartworms live in the bloodstream. As they begin to die, they dislodge from the blood vessels and move freely within the blood.

Heartworms can get lodged or stuck in blood vessels which will cause an obstruction. This will typically occur in the lungs, causing breathing problems. It is very important to keep your dog quiet and calm during the entire treatment. Your dog needs to be rested for 6-8 weeks after the third and final injection

Six months after the third injection, we will test your dog for heartworm disease. Hopefully, they will be heartworm-free, but sometimes dogs can still be infected. We will discuss with you how to manage that if that happens.

It is MANDATORY that your dog stays on heartworm prevention during treatment and for the rest of their lives. There can be permanent damage to the heart and lungs after a heartworm infection. If your dog becomes infected again, it can further that damage and even kill them!

Heartworm Appointments

This is the initial exam performed to determine the overall health of your dog and to determine if your dog will be healthy enough to undergo heartworm treatment.

Bloodwork will be performed to confirm heartworm disease and assess other bodily functions
If the veterinarian approves your dog for treatment, your dog will be prescribed doxycycline (antibiotic) for 28 days and heartworm prevention.

First Visit

  • You will arrive between 8-9 a.m. on your scheduled day to drop off your dog.
  • Your dog will be evaluated again by the veterinarian to make sure they are healthy enough for heartworm treatment
  • Your dog will be given prednisone and a muscle relaxant, then injected with the heartworm treatment.
  • We will continue to monitor your dog throughout the day for any adverse reactions.
  • Your dog will go home with 28 days of prednisone (steroid)
  • Plan to pick your dog up between 4-5 p.m. that night.

Second/Third Visit

  • Thirty days after the first visit, your dog will be scheduled for the second and third injections. These are injections given one day apart.
  • The procedure will be the same as for the first visit.
  • Your dog will go home on another 28 days of prednisone
  • You can pick up your dog between 4-5 p.m. after the second injection and then bring them back the next day in the morning between 8-9 a.m. for the third injection

Canine Heartworm Treatment

Includes antibiotics, blood work, muscle relaxers, Immiticide, and one year of heartworm prevention

2 – 25 lbs. – $497
26 – 50 lbs. – $609
51 – 100 lbs. – $723
100 – 125 lbs. – $977

Prices are subject to change without notice.

Important Home After Treatment Information

Crate for confinement – especially when you are not at home. If you are at home and your dog will rest quietly on the couch or nearby, they may do so. Absolutely NO roughhousing with other animals, kids, visitors, chasing toys, etc.

Leash walk -please walk your dog on a leash when going outside for bathroom breaks

Warm compresses 5-10 minutes several times daily as needed for additional pain relief. These can be made by placing uncooked rice in a tube sock and knotting the end, then heated in the microwave until warm but not hot. A good rule of thumb is that if it is too hot to put on a baby, it’s too hot for a dog! Always place a thin cloth/paper towel between the skin and the compress.

Things to watch for

If you notice these in your dog after a treatment, please call us immediately:

  • Coughing (+/- blood or pink-tinged fluid)
  • Difficulty breathing
  • Nosebleeds
  • Excessive swelling, redness, pain, or discharge at the injection site.
  • Vomiting and or diarrhea

If it is after hours, please contact an emergency clinic:
Suncoast Veterinary Emergency at 855-843-0858.  The Veterinary Emergency Center is located at 4937 S. Tamiami Tr. Sarasota, FL 34231.

Please note — approximately 30 percent of dogs treated for heartworms will experience some form of reaction at the injection site. This could be swelling, redness, tenderness, warm to the touch, or even a firm lump. Most will resolve quickly but could take up to 30 days. A smaller percentage of dogs will have a permanent small firm lump at the injection site.