I Gave My Dog Heartworm Pill Early [Is Your Dog At Risk?]

Zack Keithy, our author, is a certified veterinarian technician (UC Blue Ash) for over 6 years (contact him here). The articles written here are based on his expertise and experience, combined with a review by our expert vet reviewers including Dr M. Tarantino. Learn more about us here.

We’ve all been there, a moment of forgetfulness, a slip of schedule, and now you’re screaming “I gave my dog heartworm pill early!”

An icy shiver of panic grips you. Are they at risk?

Before you panic, take a moment to breathe.

Let’s find out what happens if you give your dog heartworm medication ahead of schedule and learn what you can do now.

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Do I Have to Give My Dog Heartworm Medication on the Same Day Every Month?

Heartworm medication is an important tool in preventing heartworm disease in dogs, a serious illness caused by mosquito bites.

It works by killing off the immature heartworm larvae, preventing them from growing into full-blown troublemakers.

To keep your pet safe from these yucky parasites, it’s generally recommended to give them their monthly heartworm medication on the same day. 

But hey, life happens, and sometimes we miss the exact day or need to give the medication a bit earlier.

No need to panic! A slight deviation from the schedule won’t send your pet to the vet.

Giving the medication a few days ahead or behind the scheduled date is not going to harm your pet.

So, breathe easy! Just remember that consistency is still important for long-term protection. 

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Can I Give My Dog Heartworm Medicine a Few Days Early?

Can I Give My Dog Heartworm Medicine a Few Days Early

Yes, you can give your dog heartworm medicine a few days earlier than scheduled.

Doing so is generally considered safe and won’t cause any health-threatening problems.

Some vets say that you can give it 5 to 10 days in advance and it wouldn’t be a big problem.

Giving the medication a few days early ensures that your dog remains protected without any gaps in their heartworm prevention.

The bigger problem is when you give the medication late, like more than a few days.

It exposes your furry pal to the risk of harmful heartworm parasites developing into adults, at which point the medicine is ineffective in getting rid of them.

Alternatively, you can consider switching to Advantage Multi, which still works even if you have a lapse in applying it.

Advantage Multi

Provides heartworm disease prevention, forgiving occasional lapses in the monthly schedule.
If you forget and exceed 30 days between applications, treat immediately and return to your regular monthly routine.
Not only prevents heartworms but also kills adult fleas on contact, eliminating the need for them to bite your dog.
Also treats sarcoptes, a skin mite causing intense itchiness, which can also affect humans

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When Should You Give a Dog Heartworm Treatment?

Heartworm treatment should be given as a preventive measure, ideally starting at six to eight weeks of age for pups. 

Many vets also recommend year-round prevention which means giving your pet 12 months of heartworm medication and getting them tested annually.

You’ll need to ask your pet’s vet to find out what type of treatment will suit your furry pal.

Alternatively, you may also speak to an online vet to save you the hassle of making a trip to the office.

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How Long Should You Give a Dog Heartworm Treatment?

The duration of the heartworm treatment will depend on the specific medication the vet prescribes to your pet.

The prevalence of heartworm disease in your area can also be a factor.

Generally, heartworm treatment is administered year-round. This is to ensure that your furry pal is protected against the infection all the time.

This is extra crucial in places where mosquitoes are active throughout the year.

Consistent protection needs to stay in place even during the cooler months when mosquito activities tend to decrease.

What Happens if You Give Heartworm Medicine Before the Next Dose is Up?

Nothing bad will happen if you give your pet their medicine against heartworm before the next dose is up. 

In fact, even if you accidentally give them one to two tablets more than the recommended dosage, it shouldn’t lead to an emergency trip to the vet’s clinic. 

What Should You Do if You Gave Your Dog Heartworm Medicine Early?

If you accidentally gave your dog heartworm meds early, there’s no need to panic as it’s generally safe and unlikely to cause harm. 

Simply resume the regular dosing schedule a month after and continue with the recommended monthly administration.

Skipping a dose or doubling up on medication is typically unnecessary and may mess up the effectiveness of the treatment. 

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A Few Simple Tips to Ensure Proper Administration of Heartworm Medication

If you tend to forget medication dates and keep track of things, no worries! Try these clever tricks to stay on top of your furry friend’s heartworm medication schedule.

  • First, create a reminder using a system that works for you. Use your phone’s alarms or calendar notifications. You can even use cute sticky notes. Most importantly, find a method that catches your attention and helps you remember those important monthly doses.
  • Next, be sure to carefully read and follow the instructions provided by the med’s manufacturer and your veterinarian. Pay close attention to dosage guidelines, storage requirements, and any specific administration instructions. This will ensure that you are giving the medication to your pet correctly. 
  • Certain dog breeds are a little more sensitive to the active ingredients in the meds. So, never give your pet more than the recommended dosage if they are a Border Collie, Old English Sheepdog, or a German Shepherd.
  • To make things easier, incorporate the administration of the heartworm medication into your pet’s routine. Choose a time that’s easy to remember, like during mealtime or before your pet’s walk. Maybe bring it with you to your pet’s monthly session with the groomer. Making it a part of your regular activities will help it become second nature.
  • Keeping records of each dose administered is also important. Note down the date and the specific brand or type of medication used. This will help you track your dog’s heartworm prevention history and provide useful information for future reference. I recommend you use a dog care planner to help you out.

Frequently Asked Questions (FAQs)

Can a dog overdose on heartworm medication?

While accidental ingestion of one or two extra tablets of heartworm medication is unlikely to cause an overdose in most dogs, it’s essential to note that larger amounts or prolonged exposure to higher doses can be harmful. 

What if I accidentally gave my dog two heartworm pills?

Accidentally giving your dog two heartworm pills should not cause an adverse reaction. However, if your pet starts drooling, having difficulty breathing or walking, becomes disoriented, or starts seizing, seek immediate veterinary care at an emergency clinic.

Can I give my dog heartworm medicine every 45 days?

It’s important to give your dog heartworm medicine on a monthly basis, around every 30 days, to ensure they stay protected. Delaying the medication leaves your dog vulnerable, allowing heartworm larvae to develop into adult worms, leading to potential health problems. Stick to the recommended schedule for their safety.

How long does it take for heartworm medicine to wear off?

The active ingredients in heartworm medication, such as ivermectin or milbemycin oxime, usually stay in a dog’s system for approximately 24 to 48 hours. This duration is sufficient to eliminate any heartworm larvae that may have developed during the 30-day treatment cycle, providing effective protection against heartworm infection.

Can you give Interceptor Plus early?

Yes, you can give Interceptor Plus a few days earlier than the scheduled dosage, but it’s important to reset the dosing schedule accordingly to maintain the 30-day interval between doses.

Is it okay to give Heartgard early?

Yes, it is generally okay to give Heartgard early. However, if you do this, you’ll need to adjust the dosing schedule accordingly. You’d need to give the next dosage 30 days after the previous one instead of the original schedule.

In Conclusion: Gave My Dog Heartworm Pill Early

Look, this hiccup doesn’t make you any less of a caring pet parent.

We’ve all journeyed through the mistakes we make, consulted with vets, and learned prevention strategies.

So let’s transform our worries into awareness because our fur-babies deserve the best!

If this article helped you, please share it with other pet parents who might be facing the same conundrum.

Meanwhile, check out these other dog care articles too:

You’ve made it to the end, but I hope it’s not the end of our journey. We want to hear your voice! Share your thoughts, problems, suggestions, or anything related to your dog in the comments section. And don’t forget to join our newsletter today too.

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Zack Keithy
Zack Keithy

Hey, I'm Zack, the Chief Editor here. I was formerly a Certified Veterinary Technician (CVT) for a good 6 years before moving on to greener pastures. Right now, I am still heavily involved in dog parenting duties, and it is my desire to share all our knowledge with fellow dog owners out there! Connect with me on LinkedIn, or read more about Daily Dog Drama!

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