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.
Less than 2 weeks: Give your dog the missed dose immediately. 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.
A: Give the dose you missed immediately, then continue giving the medication on the day you've always given it. If the missed dose is more than 2 weeks late, your dog should be tested for heartworm again in six months (click here to learn why). Want a free monthly reminder so you don't forget to give preventatives?
Heartworm medications are highly effective, but dogs can still become infected. If you miss just one dose of a monthly medication—or give it late—it can leave your dog unprotected. Even if you give the medication as recommended, your dog may spit out or vomit a heartworm pill—or rub off a topical medication.
If you miss a monthly dose, the heartworm larvae are given the opportunity to reach a mature state that cannot be affected by the preventive. Giving your dog his heartworm preventive on the same date each month will affect the larval stages he acquired since his last heartworm preventive dose.
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. In this case, it would be fine to just resume giving your pet heartworm prevention medication as usual.
2 – There is a (small) grace period with heartworm preventatives. Because it takes 40-50 days for the larvae to mature past the point of no return, we could in theory give preventative every 40-50 days right? Yes, you could.
HEARTGARD Chewables should be given at monthly intervals during the period of the year when mosquitoes (vectors), potentially carrying infective heartworm larvae, are active. The initial dose must be given within a month (30 days) after the dog's first exposure to mosquitoes.
However, if you do miss a dose, give it as soon as you remember. Then, adjust the dosing schedule so that the next dose is 30 days after the new dose. Never administer two doses at once or give extra doses.
Although dogs are still protected from heartworm disease up to 2 weeks after the first missed dose, its efficacy is reduced and your dog's risk of developing heartworm disease is increased. Administer Heartgard immediately and return to the previous dosage schedule.
SIMPARICA TRIO should be administered at monthly intervals year‑round or at least within one month of the animal's first seasonal exposure to mosquitoes and continuing until at least 1 month after the dog's last seasonal exposure. If a dose is missed, give SIMPARICA TRIO immediately and resume monthly dosing.
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.
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.
Although there are fewer mosquitoes in the winter, there is still a risk that your pet could get heartworms if you stop giving heartworm prevention medication during this season. That's one reason veterinarians strongly recommend pets receive heartworm prevention medication year-round.
How Often To Give Heartworm Drugs. Most heartworm drugs come with instructions to give them every 30 days. But according to many holistic vets, the monthly drugs are just as effective if you give them every 45 days, and 99 percent as effective if given every 60 days.
If you miss a dose of Simparica Trio, give it immediately and resume monthly dosing. Contact your vet if your dog misses a month or more of heartworm prevention—your dog might have become infected with heartworm larvae.
If you miss that monthly dose, your pet is at a potential risk of getting flea or tick bites, which can transmit some serious diseases. Heartworm preventive medicine is especially important to keep on schedule for your pet.
Dosing Schedule:
If a dose is missed, administer NexGard and resume a monthly dosing schedule. Flea Treatment and Prevention: Treatment with NexGard may begin at any time of the year. In areas where fleas are common year-round, monthly treatment with NexGard should continue the entire year without interruption.
May be given with or without food. If your animal vomits or acts sick after receiving the drug on an empty stomach, try giving the next dose with food or a small treat. If vomiting continues, contact your veterinarian.
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.
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.
General dosing guidelines follow. For dogs: Dose is 0.0015 to 0.003 mg per pound (0.003 to 0.006 mg/kg) once a month for heartworm prevention; 0.15 mg per pound (0.3 mg/kg) once, then repeat in 14 days for skin parasites; and 0.1 mg per pound (0.2 mg/kg) once for gastrointestinal parasites.
If you miss a dose of your heartworm prevention for your dog, get them back on prevention ASAP—speak to your veterinarian. Six months from that time that you missed is really the only time that we're going to be able to detect whether or not your dog was infected during that period.
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.