Ask Alice: Are Year-Round Heartworm and Tick Preventative Necessary?

We think of our pets as family so when they get sick we panic and have a million questions. Well, no fear, Dr. Alice Weiss is here! Dr. Weiss has been working for 30 years as a licensed veterinarian and is here to answer any questions you may have about your best furry friends.

If you have a question for Dr. Alice about your pet, email it to:


Dear Dr. Alice,
When do I start back up on the heartworm medication for my dog? He actually loves the chewable ones but they are so expensive. So I wanted to know when I really have to give it to him.
Thanks, Rover’s family

Dear Rover’s Family,
Good question. Heartworm parasite is a nasty worm that as an adult lives in the dog’s heart chamber and obviously is very dangerous. The adult sheds baby heartworms which are called microfilaria and are microscopic in the blood stream. Mosquitos feed on the contaminated dog and when they feed on the next dog who does not have heartworm disease, the microfilaria gets put into the new dog’s blood stream. Hopefully, the new dog is on the preventative medication which kills the newly deposited microfilaria. So, technically, you would put the dogs on the preventative in the mosquito season. However, if you live in an area with mild winters, I would keep them on the preventatives all year round. You don’t want to take a chance with this parasite.


Dear Dr. Alice,
My veterinarian wants to sell me some anti-tick medication but it is so expensive. Is that necessary? We live in a condo right outside the city and are there ticks around?
Sincerely, Tick Questioner

Dear Tick Questioner,
The warmer weather brings out more ticks. If your dog goes out to dog parks or parks, ticks may be able to jump from dog to dog or from a piece of grass to dog. Really any species of tick can have a transmittable disease to your dog and to you. If your dog’s fur is thin enough to allow you to check for ticks after walks, and you have more concrete versus grass outside your condo then I wouldn’t rush out to buy the medication. But, keep a watch out for the little suckers. I have to admit ticks might be the only being that disgusts me.

Read more of Dr. Alice’s sage advice here.

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Dr. Alice has spent her life embracing and advocating the animal human bond through her work as a traditional and a public health veterinarian, a writer, and vlogger on dogsenjoylife. Some people love expensive vacations and shopping but all Dr. Alice needs is time with her pets.

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