Get

In Your Inbox

Dogster is reader-supported. When you buy via links on our site, we may earn an affiliate commission at no cost to you. Learn more.

Lepto Vaccine for Dogs: What to Know & Side Effects (Vet Answer)

black dachshund getting a vaccine

Vaccinations generally provide good protection for your dog against certain diseases that could be severe and debilitating. While no vaccine leads to 100% immunity, it lessens the severity of the signs and improves recovery time should the disease be contracted. Some diseases are zoonotic, meaning they can be transmitted from animals to people. These include the rabies virus and leptospirosis. Vaccinations designed for animals that prevent transmissible diseases to people are essential in reducing public health threats. Keeping both pets and people healthy is a priority.

divider dog faces oct 2024

What Is the Leptospirosis Vaccine?

Leptospirosis is a disease caused by the bacterium Leptospira, found in both water and soil. The bacteria is more common in warm climates with high yearly rainfall averages, but it can proliferate anywhere after heavy rain and flooding. In the United States, infection rates in dogs seem to be higher in the southwestern, midwestern, and eastern regions.

All dogs are at risk of infection from leptospirosis, especially those that may come in contact with contaminated urine via:

  • Drinking from slow-moving or stagnant water sources, such as ponds, lakes, and streams
  • Exploring rural properties with exposure to infected farm animals and wildlife
  • Contact from potentially other infected dogs, such as at dog parks and boarding and training facilities
  • Contact with rodents

Leptospirosis can lead to kidney and liver failure and sometimes, severe lung disease, which causes difficulty breathing. This disease, even if treated, can be fatal.

Fortunately, a leptospirosis vaccine is available to help protect your dog and loved ones from this potentially life-threatening disease. It is recommended that all dogs be vaccinated to help protect them from infection.

Cute Labrador puppy getting a vaccine
Image by: ARVD73, Shutterstock

How Is the Leptospirosis Vaccine Given?

This vaccination is given under the skin (subcutaneously) and may be administered alone as its own separate vaccine or in combination with the distemper/parvo vaccine (DA2LPPv). Dogs 12 weeks of age and older can start the vaccination series. The initial series involves a set of two vaccinations, spaced 2–4 weeks apart, and then boosted annually.

What Happens If You Miss a Vaccination Dose?

If a dose is missed in an initial vaccination series, the series can be restarted with one vaccination given, followed by another given 2–4 weeks later to stimulate an appropriate immune response. The vaccination is recommended to be given annually after the initial series is completed, and if the annual booster is missed, it is recommended to booster as soon as possible.

divider dog faces oct 2024

Potential Side Effects of the Leptospirosis Vaccine

The leptospirosis vaccine has been shown to have a similar frequency of side effects or adverse reactions as other vaccinations commonly given to dogs. The results from a large study involving over 1 million dogs showed that the rate of adverse reactions to the lepto vaccine was 0.3%. The benefits of vaccination far outweigh the risks, as leptospirosis is a life-threatening disease that can affect any dog worldwide. If you’re concerned about potential side effects, it’s best to discuss them with a vet. As with any vaccine, common temporary side effects may include:

  • Pain and tenderness at the injection site
  • Lethargy
  • Mild fever
  • Decreased appetite

More serious and potentially life-threatening side effects can include an anaphylactic reaction, which may produce signs like:

  • Vomiting or diarrhea
  • Hives
  • Facial swelling
  • Difficulty breathing
  • Collapse

It is advised to seek immediate veterinary care if you notice any of these signs.

Did you know you can speak to a veterinarian without having to travel? Just head over to PangoVet. It's our online service where you can talk to a vet online and get the advice you need for your pet — all at an affordable price!

PangoVet_Mention-in-Content Savings V1

divider dog faces oct 2024

Frequently Asked Questions (FAQ)

At What Age Can My Dog Get the Leptospirosis Vaccine?

Dogs 12 weeks and older can start the initial vaccination series.

How Often Is the Leptospirosis Vaccine Boosted?

The current recommendation is to boost annually.

Is the Leptospirosis Vaccine More Dangerous Than Other Vaccines?

No, the leptospirosis vaccine has not been shown to have an increase in side effects after administration. Although this is considered a non-core vaccine, all dogs should be vaccinated for leptospirosis because it can be a potentially life-threatening disease and may be transmissible to people.

divider dog faces oct 2024

Conclusion

While the leptospirosis vaccine is considered a non-core vaccine for canines, it is recommended that all dogs should receive it. Leptospira bacteria can be found in contaminated soil and water sources, especially in infected urine. Dogs with leptospirosis may experience kidney and liver failure and may develop breathing difficulties, which can be fatal. This disease is also zoonotic, meaning it can be transmitted to people, so a vaccinated dog also protects the entire household.

Also see:


Featured Image Credit: Masarik, Shutterstock

Want content like this delivered to you?

Sign Up For Our Newsletter

News, insights, expert advice, and everything dog

* By submitting, you agree to our Terms & Conditions and Privacy & Cookies Policy.


How useful was this post?

Click on a star to rate (you can leave written feedback after clicking submit)

Help us improve Dogster for pet parents!

Your feedback really matters.

What did you like about this post? Also how can we improve it?

Join the conversation

6 Responses

  1. After our 6 lb yorkie got the leptovirus injection she will go up to 4 days without eating and has become mentally different. Why!!

    1. Hello Rita,

      Thank you for reaching out and sorry for a late reply. We are very sorry to hear about your Yorkie! In these cases it is always best to immediately contact the veterinarian who administered the vaccine and tell them about the signs.
      We hope that your dog is alright!

  2. My dog collapsed two days after getting this vaccine. She has never had a problem with it before and was wondering if this could have been the problem. She was taken to emergency vet and we are not sure if she had a seizure or if some other episode occurred. The cost to find out was way beyond what I could afford. I am just trying to eliminate some possibilities. She is doing ok now.

    1. Hi Beth, I’m so sorry to hear about your pup—that must have been so scary. Totally understandable that you’re looking for answers, especially with the timing of the vaccine.

      The leptospirosis vaccine tends to have side effects similar to other common dog vaccines, and the risk of an adverse reaction is pretty low—around 0.3%. That said, reactions can still happen, even if they’re rare. Still, the benefits of vaccinating usually far outweigh the risks, as leptospirosis is a serious and potentially life-threatening disease. Getting to the bottom of what happened would likely require some testing, but as you mentioned, that can get expensive, and unfortunately, even with testing, we don’t always get clear answers.

      The good news is she’s doing okay now, which is a really positive sign! I’d suggest keeping an eye on her and noting any changes in appetite, behavior, or mood—just to be safe. If chatting with a vet would help ease your mind, you can book a time that works for you here: https://pangovet.com/schedule-appointment/. 🙂

  3. My border collie/lab mix received her leptosprosis vaccine last Monday. Five days later we noticed a hard bump at the injection sight. Is this a possible side effect of the vaccine?

    1. Hi Kathleen, thanks for getting in touch. A hard bump at the injection site can sometimes occur after a vaccine, and it is typically not uncommon. This could be a reaction to the injection itself, and it's usually a result of inflammation or a localized immune response. It's often referred to as an "injection site reaction."

      Most of the time, these bumps are harmless and will resolve on their own within a few days or weeks. However, if the bump doesn’t go away, becomes larger, or if your dog shows any signs of discomfort, redness, or swelling in the area, it's a good idea to have a veterinarian take a look to ensure it isn't an infection or another issue.

      If the bump doesn't seem to be causing your dog any pain and your dog is otherwise healthy and acting normal, it’s likely nothing to worry about. Just keep an eye on it and consult your vet if you're concerned. I hope this helps. 🙂

Leave a Reply

You’re very welcome to leave a comment or question. Please know that all comments must meet our community guidelines, and your email address will NOT be published. Let’s have a positive and constructive conversation.


Talk With A Vet Online

Peace of mind,
anywhere, anytime

Affordable vet advice

12 Best Dog Breeds for Single Guys: Info, Pictures, Temperament & Traits

When you’re looking for a pup as a single guy, you have a few factors to consider. You want a dog that isn’t...

Cesar Dog Food Review 2026: Pros, Cons, Recalls and Guide

Review Summary Cesar has been a staple in the pet food section of grocery and big box stores for decades. This food is...

Can You Put Neosporin on a Dog? Vet-Reviewed Safety Facts

A tube of antibiotic ointment Neosporin is handy to keep around for minor injuries, but is it safe to put on a dog?...

Why Does My Dog Steal My Shoes? 6 Likely Reasons & Tips

You go to grab your favorite sneakers and find that one is missing. You eventually find it in your dog’s bed. Or maybe...

More related

How to Boost Your Dog’s Immune System: 7 Vet-Reviewed Natural & Safe Ways

As dog parents, we want our pups always to stay healthy, and the immune system is a crucial component of good health in...

9 Great Off-Leash Dog Parks in Charlotte, NC in 2026 (With Pictures)

Humans have plenty of places to socialize and enjoy, but what about your pups? If you live in or are visiting Charlotte, North...

How Much Does Dog Patellar Luxation Surgery Cost? Vet Reviewed FAQ

A patellar luxation, also known as a luxating patella, occurs when a dog’s kneecap moves out from the position it should normally be...

4 Best Vet-Approved Dog Vitamins in 2026 – Reviews & Top Picks

Our canine pals are members of our families like anyone else, so of course, keeping them healthy and thriving is our top priority....

Keep reading

Can Dogs Eat Mint? Vet Approved Facts & FAQ

What do you think of when you think of mint? Fresh breath, spruced-up salads, smoothies, and mojitos. But have you ever wondered if your dog can have mint? Smelly dog breath is a common complaint, so is it okay to...

can dogs eat mint

Castor & Pollux Dog Food Review 2026: Pros, Cons, Recalls, and FAQ

Review Summary Please note that several Castor & Pollux products are currently unavailable. At this time, we are unsure whether these items have been fully discontinued, are experiencing supply issues, or if there is another reason for their absence. We...

Dogster_Castor & Pollux Dog Food Review

Can Dogs Drink Pool Water? Dangers Of Chlorine & Saltwater

Some dogs are born natural swimmers,1 such as the Labrador Retriever, Portuguese Water Dog, and Otterhound. Freshwater water bodies can be hazardous since giardia can harm dogs and people.2 When you’re talking about pool water, it’s another story. The chemicals...

Can Dogs Drink Pool Water

Buying Dog Food In Bulk: Benefits & Risks

According to statistics, the typical American dog owner spends an average of $1,380 annually on their dog’s basic expenses.1 While our pooches deserve the world, $1,380 is a lot. As such, any avenue that allows us to save on pet...

dog food_Shutterstock_Ekaterina Markelova

10 Best High Fiber Dog Foods for Constipation in 2026 – Reviews & Top Picks

If you have a pup who is constantly constipated on your hands, then you’re likely desperate for a solution (especially if nothing you’ve tried thus far seems to have helped). That’s where high fiber dog foods come in. Though it’s...

german shepherd dog lying near food bowl

10 Best Puppy Foods for Labs in 2026 – Reviews & Top Picks

So, you are on the hunt for the best food for your brand-new Lab puppy. Choosing the best puppy food for your new puppy is a very important decision, since getting the proper nutrition is important for bone development and...

labrador retriever puppy eating food from bowl outdoors

10 Best Dog Foods for Loose Stools in 2026: Reviews & Top Picks

Picking up after our dogs is one of the least enjoyable aspects of canine ownership. But this task is made even harder if your dog consistently produces stool too loose to be easily collected in a poop bag. If we...

boston terrier dog holding a bowl of food

How to Boil Chicken for Dogs: A 5-Step Vet-Approved Guide

Good nutrition is important to not only human beings but animals as well. It’s the reason why their bodies can fight foreign invaders such as fungi, parasites, viruses, and even bacteria daily. Chicken is a great, healthy food for dogs—provided...

pieces of white chicken meat are boiled in a saucepan