Is A Heartworm Test Necessary Every Year?

Last updated: March 5, 2019

Most heartworm preventatives are very effective. So why is it important that your pet receives a yearly heartworm test? Although heartworm is a preventable disease, there are several factors that may mean your pet is not as protected as you think. Here are a few:

1. Missing a Dose. We are all human and may forget to give a dose every now and again.


2. Your pet vomits or spits out the pill without you knowing it.


3. Your dog goes swimming immediately after a topical heartworm preventative is applied.


4. Your pet builds up a resistance. Heartworm preventatives are effective but resistance is still possible. Having a yearly test done allows your veterinarian to know when there is a resistant worm and treat your pet more effectively.


5. Testing limitations. Since heartworm larvae can't be detected on a heartworm test until they become adults, there is a timeframe where those worms are not found on a test or stopped by a preventative. If your pet goes undiagnosed, a heartworm infection can damage the heart, lungs, vascular and kidney tissues.


6. Heartworm is carried by infected mosquitos. Since mosquitos can survive indoors and outdoors in protected areas, only treating during the summer months may lead to animals becoming infected unintentionally. That is why seasonal heartworm treatment is not recommended.

Thankfully, heartworm testing is easy and inexpensive. Your veterinarian can check your pet with a simple blood test at his annual visit. Revival has several heartworm preventatives available through our pharmacy including Heartgard^{® Plus}, Revolution^®, Sentinel^® and Interceptor™ Plus. To see our full line of heartworm prevention products visit the Revival online pharmacy or give us a call at 800.786.4751

- Lori, Pharm. D.

Lori Sheehan, Doctor of Pharmacy, received her Doctor of Pharmacy degree in 2009 from Creighton University. She's previously worked as a retail pharmacist and owned her own long-term care pharmacy from 2013 to 2016. Lori has served as Revival's Pharmacist in Charge since 2017. Lori lives on a farm with cats, calves and her dog, Lucky.

The materials, information and answers provided through this website are not intended to replace the medical advice or services of your personal veterinarian or other pet health care professional. Consult your own veterinarian for answers to specific medical questions, including diagnosis, treatment, therapy or medical attention.