Experienced and professional animal trainer provide their insights in answering this question :
A. Pills for heart worms kill also other worms and parasites. They are very effective and have broad spectrum, thet is why they have been given to you for a stray cat with unknown past and heath record.

How to Identify Common Pet Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced pet care professionals :

If a heartworm-positive dog is not tested before starting a preventive, the dog will remain infected with adult heartworms until it gets sick enough to show symptoms. Heartworm preventives do not kill adult heartworms. Also, giving a heartworm preventive to a dog infected with adult heartworms may be harmful or deadly.
The American Heartworm Society recommends annual heartworm testing. It`s important to never give Heartgard to any pet that has not been tested for heartworm disease. Heartworm preventative medication such as Heartgard cannot kill adult heartworms, but instead kills the baby heartworms known as microfilariae.
It`s possible, but not likely for your pet to develop heartworm disease if you give them a preventative. The most common reasons pets get heartworm is because of a skipped or late dose. Remember, heartworm preventative only kills larvae in your pet`s bloodstream.
Generic Ivermectin

You can prevent heartworm disease by using the same medication sold by drug companies for a fraction of the price. If you have a large dog, you can order the generic ivermectin from Amazon.com. (I have large dogs, so this is the form of ivermectin that I give them to prevent heartworm disease.)

Most of the monthly heartworm medicines have a safety factor of at least 15 days of protection if a dose is missed. This means that if you`re just a week or two late, your pet is likely still within that window of protection and would be unlikely to become infected during that time.
Signs of heartworm disease may include a mild persistent cough, reluctance to exercise, fatigue after moderate activity, decreased appetite, and weight loss. As heartworm disease progresses, pets may develop heart failure and the appearance of a swollen belly due to excess fluid in the abdomen.
testing should be done routinely regardless of how diligent you are about giving your dog preventatives. A dose within the 6 month larva/egg cycle of heartworms will generally kill them, so a missed dose on a monthly regimine isn`t quite as doom and gloom as you`re making it sound.
If you live in an area with a high incidence of infection, I would recommend using heartworm prevention. In my practice, I use an ivermectin products like Heartgard. The dose of ivermectin needed to prevent a heartworm infection is very small and safe (more on this later).
If you forget a month of preventative, make sure to give the next 2 doses on time to “catch up” for that missed month. If you miss several months in a row, you should give your vet a call for advice on when to plan for the next heartworm test and how to get started back on preventatives.
Heartworm preventatives are generally given as a monthly dose and are available in several different types. These include monthly pills that you can hide in his food and topical treatments that you place on his skin that will deter mosquitos.
As winter descends upon New England in full force, more and more dog owners ask us if we recommend continuing heartworm prevention through the winter months. The short answer is yes. The American Heartworm Society recommends year-round heartworm prevention, and we agree.
Heartworm infection can become severe if left untreated with life-threatening health conditions and even death.
No one wants to hear that their dog has heartworm, but the good news is that most infected dogs can be successfully treated. The goal is to first stabilize your dog if he is showing signs of disease, then kill all adult and immature worms while keeping the side effects of treatment to a minimum.
Myth #3: If my pet has heartworms, I will see them in her feces. Although many worm types, such as roundworms and tiny hookworms, are shed in your pet`s feces, heartworms do not live in the gastrointestinal (GI) tract, and are not found in feces.
Puppies can begin heartworm preventative medication from as young as 6/8 weeks old. If your pup is a little older (age 6 months plus) it is important that she is given a heartworm test before preventative medication is given.
In a word, yes. Heartworm testing is very important to the health of your dog. If your dog is heartworm positive and you put it on certain types of heartworm preventative, it could have detrimental effects, including death.
Heartworm disease can be prevented in dogs and cats by giving them medication once a month that also controls various internal and external parasites. Heartworm infections are diagnosed in about 250,000 dogs each year. 1 But there is no good reason for dogs to receive preventives all year; it is just not needed.
Do I need a prescription for my pet`s heartworm preventive medication? If so, why? Yes. The U.S. Food and Drug Administration (FDA) labeling on heartworm preventives states that the medication is to be used by or on the order of a licensed veterinarian.
Having these drugs available as prescription-only medications ensures that they are used appropriately. For example, heartworm preventatives are labeled as “prescription-only” because it`s critical that your veterinarian makes sure the medication is the right one based on your pet`s health status.
Your dog will be protected from heartworm disease because you will still be within the 45-day grace period in which the preventative is effective. Resume your normal monthly dosing schedule. 2.) More than 2 weeks: Contact your veterinarian because you are likely outside of the grace period.
Interceptor is the ONLY safe heartworm prevention medication for Collies, Collie-mixes, Shelties and Sheltie-mixes. This is because Interceptor does not contain the drug ivermectin, which is known to have deadly effects in these and some other breeds. Heartworm prevention is easy.
Many flea and tick medications are manufactured in a once-monthly topical application or pill. If you miss that monthly dose, your pet is at risk of getting flea or tick bites.
Heartgard® Overdose Information

Signs of an overdose include drooling, incoordination, weakness, tremors, disorientation, lethargy, dilated pupils, blindness, coma, and death. Other symptoms may include vomiting, diarrhea, low heart rate, body temperature changes and abnormal behavior.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. Whenever I take my dog on walks he always barks at people and others dogs in my neighborhood. What should I do to resolve the problem
ANSWER : A. The very first thing to do is to make sure your dog is getting sufficient physical and mental exercise every day. A tired dog is a good, happy dog and one who is less likely to bark from boredom or frustration. Depending on his breed, age, and health, your dog may require several long walks as well as a good game of chasing the ball and playing with some interactive toys.

Figure out what he gets out of barking and remove it. Don’t give your dog the opportunity to continue the barking behavior.

Ignore your dog’s barking for as long as it takes him to stop. That means don’t give him attention at all while he’s barking. Your attention only rewards him for being noisy. Don’t talk to, don’t touch, or even look at him. When he finally quiets, even to take a breath, reward him with a treat. To be successful with this method, you must wait as long as it takes for him to stop barking. Yelling at him is the equivalent of barking with him.

Get your dog accustomed to whatever causes him to bark. Start with whatever makes him bark at a distance. It must be far enough away that he doesn’t bark when he sees it. Feed him lots of good treats. Move the stimulus a little closer (perhaps as little as a few inches or a few feet to start) and feed treats. If the stimulus moves out of sight, stop giving your dog treats. You want your dog to learn that the appearance of the stimulus leads to good things.

Teach your dog the ‘quiet’ command. Oddly, the first step is to teach your dog to bark on command. Give your dog the command to “speak,” wait for him to bark two or three times, and then stick a tasty treat in front of his nose. When he stops barking to sniff the treat, praise him and give him the treat. Repeat until he starts barking as soon as you say “speak.” Once your dog can reliably bark on command, teach him the “quiet” command. In a calm environment with no distractions, tell him to “speak.” When he starts barking, say “quiet” and stick a treat in front of his nose. Praise him for being quiet and give him the treat.

As in all training, always end training on a good note, even if it is just for obeying something very simple, like the ‘sit’ command. If you dog regresses in training, go back to the last thing he did successfully and reinforce that before moving on again. Keep sessions short, 15-20 minutes max, and do this several times a day.

Q. Vet is saying our dog has heartworm based on a sonogram. All tests are negative and he has no cough. I am very confused
ANSWER : A. Very rarely, a dog can have a heartworm infection and still test negative on an antigen test since the antigen tested for is produced only by the female worms. If the heartworms were not fully mature, or there were only male worms present, the antigen test result in infected animals would be falsely negative. This means the test result is negative when the animal is really infected.

An antibody test will be positive even if only one male worm is present. But this test has a downfall, too. Although it is very good at giving positive results when an infection is present, a positive antibody test just means the animal has been exposed to heartworms, but may or may not currently have heartworm disease. A negative antibody test means the animal has never been exposed to heartworms.

If they are actually seeing the heartworms via ultrasound, I would follow precautions by restricting exercise. This requirement might be difficult to adhere to, especially if your dog is accustomed to being active. But your dog’s normal physical activities must be restricted as soon as the diagnosis is confirmed, because physical exertion increases the rate at which the heartworms cause damage in the heart and lungs. The more severe the symptoms, the less activity your dog should have. And the diagnosis should be confirmed. Once a dog tests positive on an antigen test, the diagnosis should be confirmed with an additional—and different—test. Because the treatment regimen for heartworm is both expensive and complex, your veterinarian will want to be absolutely sure that treatment is necessary.

Q. Does a 2 yr old dog have to be tested two times a year for heart worms when the first test was good
ANSWER : A. The heart worm test does need to be repeated if your dog was not on heart worm medication consistently every month through out the year. If your dog had it’s heart worm medication every month without fail, it may not be important to do bi-annual heart worm screenings unless you are concerned about Lyme disease. (The heart worm test will also test for Lyme and a few other tick borne diseases)

Q. What can I do to stop my dog from barking at people and front doors?
ANSWER : A. Ignore your dog’s barking for as long as it takes him to stop. This means don’t give him any attention at all while he’s barking. Your attention only rewards him for being noisy. Don’t talk to him, don’t touch him, and don’t even look at him. When he finally quiets down, even to take a breath, reward him with a treat. To be successful with this method, you must wait as long as it takes for him to stop barking. If he barks for an hour and you finally get so frustrated that you yell at him to be quiet, the next time he’ll probably bark for an hour and a half. Dogs learns that if they bark long enough you’ll give them attention.

Teach your dog the ‘quiet’ command. It may sound nonsensical, but the first step is to teach your dog to bark on command. Give your dog the command to “speak,” wait for him to bark two or three times, and then stick a tasty treat in front of his nose. When he stops barking to sniff the treat, praise him and give him the treat. Repeat until he starts barking as soon as you say “speak.” Once your dog can reliably bark on command, teach him the “quiet” command. In a calm environment with no distractions, tell him to “speak.” When he starts barking, say “quiet” and stick a treat in front of his nose. Praise him for being quiet and give him the treat.

When your dog starts barking, ask him to do something that’s incompatible with barking. Teach your dog to react to barking stimuli with something that inhibits him from barking, such as lying down in his bed.

Make sure your dog is getting sufficient physical and mental exercise every day. A tired dog is a good dog and one who is less likely to bark from boredom or frustration. Depending on his breed, age, and health, your dog may require several long walks as well as a good game of fetch and playing with interactive toys.

Q. My dog doesn’t eat, what should I do?
ANSWER : A. If this is a puppy, see a veterinarian immediately. Puppies should want to eat. Common causes for anorexia in puppies include viruses (parvo is a big one), parasitism, and foreign bodies. They need immediate care – go to an emergency vet if yours isn’t open. Puppies can get low blood sugar and dehydration very quickly.

If this is an adult dog and you observe other concerning signs, such as diarrhea or decreased energy, you should see a veterinarian.

If the dog seems otherwise bright and stable, try offering different types of food: wet food, canned tripe, or cooked chicken and rice. Some dogs will go for canned baby food: chicken, turkey, or beef as the main ingredient. Make sure there are no garlic or onions in the ingredients!

Causes of anorexia in adult dogs can range from less serious to severe. Younger dogs are more likely to get into trouble- they tend to eat things they shouldn’t, and can get foreign bodies from eating things like socks, or stomach upset from getting in the trash. Any dog may stop eating due to stress, or just being a picky eater. Middle aged dogs can stop eating when they’re stressed and also have Addison’s disease, which can be fatal. Older dogs tend to stop eating when they develop cancer or renal disease.

There is no one-size-fits-all recipe to know when the right time is to take your dog to the vet. The moral of this story is, if it’s not getting better, your pup feels bad, or you’re worried – go see the vet!

Read Full Q/A … : My Dog Won’t Eat

Q. Can giving a dog heartworm preventative to a dog that has heartworms make them sick?
ANSWER : A. YES. Never give a heartworm medication to a dog positive for heartworm unless instructed to do so by a vet.

Heartworm medications require a negative test prior to administration. This is due to the fact that giving a heartworm medication to a dog that is positive may kill off the adult worms too quickly. This can cause worms to become lodged in smaller blood vessels in the body which may lead to loss of blood to vital body parts and organs.

If your dog is heartworm positive, treatment usually involves a slow administration of medications to kill the worms under veterinary monitoring. Some vets may recommend hospitalizing a dog during their first treatment so that emergency care can be given if there is an adverse reaction or a worm becomes lodged in a vessel. A more recent procedure is to do a day-long “fast” die off of worms under monitor to prevent worms from repopulating that may occur during a longer term treatment.

Q. Husband shamed dog for having an accident inside, and now she won’t poop when he takes her out. Can we fix this? He realizes he erred
ANSWER : A. Good on your husband for realizing that scolding is not the way to potty train! Hopefully these tips can help both him and your pup get back on the right track and make pottying outside successful.

If your dog is still a puppy, that is good news as you may be able to more easily time your potty outings with your dog’s schedule. Even if your dog is older, this schedule may help. Dogs generally have to go potty about 15 minutes after eating, drinking, waking up or playing. Knowing this, get your husband to start taking out your puppy at these key times, so puppy gets used to going out with him, and the urge to potty may be higher than any fear to go. If the potty is successful, have your husband reward the dog with a favorite treat! For bowel movements, dogs may take a little more time, and you may have to stand outside for a while (sometimes even 10 minutes) to give your dog a chance to go. If she doesn’t go, take her back inside and play some, then try again in about 15 minutes. Again, a success equals a treat which most dogs will like right away!

For any indoor potty accidents that occurred, an enzymatic cleaner is great for cleaning up urine and stool. Not only does it remove the stain and smell, but it breaks down the enzymes in the urine and stool your dog can smell, which may deter her from going potty there again.

Q. Why did my vet give me heart worm preventive for a stray I took in without testing first? should I go elsewhere and get dog tested?
ANSWER : A. Pills for heart worms kill also other worms and parasites. They are very effective and have broad spectrum, thet is why they have been given to you for a stray cat with unknown past and heath record.