All physical exertion must be stopped beginning the day of the first injection, 24 hours a day, for the full 8-week period, to reduce the risk of serious (catastrophic) heartworm-related problems.
Most dogs can be safely leash-walked during the treatment recovery period and providing appropriate chew toys can help relieve some of that stored up physical energy.
Enforced Rest is ESSENTIAL! Positively NO Strenuous Exercise for 8 weeks! The heartworms will die over the next 6 weeks. As they die and are broken down, pieces of them could lodge in other parts of the body's blood vessels, causing unnecessary complications–if your pet's activity is too strenuous.
“No running, jumping, playing or high-impact exercise as these activities may cause the worms to break loose and cause significant harm to the pet being treated.”
Allowing vigorous activity at any time in these 8 weeks can cause the weakened heartworms to shatter, causing a clot of worm fragments that blocks off blood flow to the lungs, brain, or other organs (“shaking the tree” phenomenon). This causes a stroke or sudden death.
The American Heartworm Society does state that exercise restriction should begin the same day the diagnosis is confirmed. Usually, my vet instructs me to keep my heartworm positive dog from engaging in any activity that elevates the heart rate until the end of treatment.
Dogs with heartworm disease, for example, require exercise restriction before and heartworm treatment, as well as for a short time after treatment. Physical activity increases the likelihood of adult worms causing a pulmonary thromboembolism, which may be fatal. Limiting a dog's physical activity decreases this risk.
Strict rest is imperative for 6-8 weeks. This means that your pet can be leashed walked outside to urinate and defecated, but must come back inside to rest. Do not allow your pet to run, jump, climb stairs, or play rough with other dogs or children.
Rest for 60 days (ideally in a crate): Rest is the single most important factor to successful heartworm treatment. This means 4 weeks of strict rest for your dog after each melarsomine injection.
If the dog's heart rate is increased by exercise or excitement, the worm pieces can be forced into the tiny blood vessels of the lungs, increasing the chances of complications.
Prognosis: heartworm treatment success rates
With the three-dose adulticide protocol described above, in conjunction with doxycycline and macrocyclic lactones as recommended by the American Heartworm Society, 98% of dogs will be cleared of heartworm infection.
Do the heartworm treatment injections hurt? The injections are given within the muscle and can indeed be uncomfortable, but the inflammation that develops within the days following creates the most discomfort. Restlessness, panting, trembling and reduced appetite can all be signs that the dog is uncomfortable.
The medicine in the treatment (Immiticide) can cause a lot of inflammation at the injection site. This can occur no matter how smoothly things go and how little it seems to bother the dog at the time. This can range from being absolutely undetectable to a dog that is crying constantly with pain.
Additionally, you may see dead worms in your dog's stool for a few days following treatment, or your dog may have diarrhea as they digest the dead worms. Most of the time, regardless of what you see in their stool, recently dewormed dogs behave like normal.
Treatment for heartworm can cause serious complications for your pet's health and can be potentially toxic to the dog's body. Many dogs experience soreness and swelling at the site of their injections. The most severe side effects are related to a large number of worms suddenly dying.
Heartworms can also cause nosebleeds, pneumonia, high blood pressure, seizures, blindness, and excessive sleeping.
The adult worms die in a few days and start to decompose. As they break up, they are carried to the lungs where they lodge in the small blood vessels and are eventually reabsorbed by the body.
Approximately 6 months after treatment is completed, your veterinarian will perform a heartworm test to confirm that all heartworms have been eliminated. To avoid the possibility of your dog contracting heartworm disease again, you will want to administer heartworm prevention year-round for the rest of his life.
During treatment, the patient receives an intramuscular injection deep in the lower back muscles. This is a painful injection and it is common for the patient to be quite sore at home afterwards. Pain medication may be needed. The site may form an abscess, which requires warm compresses and possibly antibiotics.
Dogs can live for at least six to seven months after becoming infected with heartworms. This is because it takes that long for adult heartworms to grow.
Heartworm disease is a serious disease that results in severe lung disease, heart failure, other organ damage, and death in pets, mainly dogs, cats, and ferrets. It is caused by a parasitic worm called Dirofilaria immitis.
If your pet has received the first injection of the three injection heartworm treatment, then you will need to schedule a follow up appointment in 1 month to administer the final two injections of the heartworm treatment. Your pet will stay overnight at that time.
Dogs with heartworm disease can live high-quality lives as long as they are given appropriate care. After completing treatment and following your veterinarian's recommenda- tions on heartworm disease testing and prevention, the chances of any long-term effects are very low.
Heartworm treatment can be dangerous and difficult, especially for older dogs. The dying worms can cause significant inflammation and pulmonary thromboembolisms (i.e. clots in the lungs). Plus, the melarsomine injections can be painful and the dog must be on strict rest for months.