The common consensus is that it takes about 40‒50 days for heartworm larvae to mature to the point where heartworm preventatives no longer work. So, from the initial mosquito bite to the beginning of maturation, there is an approximate 45-day grace period that a heartworm preventative can provide protection.
What happens if you forgot to give your dog heartworm medicine?
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).
How Long Can dogs go without heartworm?
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.
Can dogs go without heartworm medicine?
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.
Can my dog miss a month of Heartgard?
Despite their best intentions, even the most attentive and diligent pet parent can occasionally forget to give their dog their monthly heartworm preventative. If this has happened to you, realize that you are not alone.
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