Doxycycline for Dogs: A Common Antibiotic to Treat Certain Infections

Doxycycline (Vibramycin) is an antibiotic. It treats a variety of bacteria that cause infections in dogs. Doxycycline usually has few side effects, but it’s not the best option for every dog. Your veterinarian will decide whether doxycycline is a good choice for your dog based on your dog’s health and the condition needing treatment.

Doxycycline (Vibramycin) for dogs at a glance

What is doxycycline for dogs, and how does it work?

Doxycycline is an antibiotic that blocks the growth of some types of bacteria. Once the bacteria stop growing, your dog’s immune system can cure the infection. Doxycycline doesn’t work against all bacteria, though. So only give doxycycline when your veterinarian prescribes it.

Doxycycline also reduces inflammation. Veterinarians use it to treat some autoimmune diseases in dogs.

What is doxycycline used for in dogs?

Veterinarians use doxycycline to treat certain bacterial infections in dogs, including:  

• Tick-borne infections (Lyme disease, Rocky Mountain spotted fever, and others)

• Kennel cough and other respiratory infections

• Some urinary tract infections

• Dental disease

• Leptospirosis 

Veterinarians also prescribe doxycycline for dogs receiving heartworm treatment. Heartworms are parasites that affect the heart and lungs of infected dogs. Heartworms often contain Wolbachia bacteria, which worsen inflammation associated with heartworm disease. Treating a heartworm-infected dog with doxycycline kills Wolbachia inside the heartworms. This reduces signs of heartworm disease and makes heartworm treatment less risky. 

Finally, veterinarians may combine doxycycline with other medications to treat autoimmune skin diseases. For example, discoid lupus erythematosus in dogs is often treated with doxycycline. 

How is doxycycline dosed and given to dogs?

Doxycycline is available in tablet and liquid form. Your veterinarian will tell you how much doxycycline to give your dog. Low doses of doxycycline treat some conditions, while other diseases need higher doses. 

Give doxycycline as directed by your veterinarian, once or twice a day. Do not change your dog’s doxycycline dose unless your veterinarian tells you to do so. 

Store doxycycline tablets at room temperature. Liquid doxycycline needs to be stored in the refrigerator. Keep this medication out of direct light. 

Finally, give your dog doxycycline tablets with food. This will reduce the risk of side effects. 

What are the common side effects of doxycycline in dogs?

Doxycycline is well tolerated by most dogs. However, side effects can occur.

The most common side effects associated with doxycycline in dogs include: 

• Loss of appetite

• Vomiting

• Diarrhea

Give doxycycline with food to reduce the risk of side effects. 

Avoid giving doxycycline to pregnant dogs. It may cause birth defects or pregnancy loss. If your pregnant dog needs doxycycline, you and your veterinarian will determine if the benefits outweigh the risks.

Veterinarians also avoid using doxycycline in young puppies. It can damage tooth enamel, leading to yellow or brown discoloration of the teeth. Nursing dogs may also pass this medication in their milk, affecting their puppies.

What are the most serious risks of doxycycline for dogs?

Doxycycline can cause liver disease in dogs. Many dogs have slightly increased liver levels while taking doxycycline. In most cases, this isn’t a serious concern. Rarely, though, doxycycline can cause liver failure. 

Signs of liver failure in dogs include:

• Jaundice (yellow skin, gums, and eyes)

• Seizures

• Abnormal bleeding

• Loss of appetite

• Vomiting

• Diarrhea

• Low energy/depression

Contact your veterinarian immediately if your dog shows signs of liver failure. And avoid using doxycycline in dogs with liver disease.

Some dogs can be allergic to doxycycline. Signs of an allergic reaction may include: 

• Rash

• Swelling

• Redness of the skin

• Trouble breathing

If your dog has an allergic reaction to doxycycline, contact your veterinarian immediately. 

Does doxycycline interact with any other dog medications?

Doxycycline can interact with other medications your dog is taking. Talk to your veterinarian about the medications your dog receives. Don’t forget to include over-the-counter medications and supplements.

Medications that may interact with doxycycline include: 

• Antacids

• Anticoagulants

• Other antibiotics, such as penicillin

• Phenobarbital and other anti-seizure medications

Talk to your veterinarian before combining any medication with doxycycline. Also, avoid giving your dog dairy products while they are taking doxycycline. Dairy products may interfere with doxycycline absorption. 

What should you do if your dog misses a dose of doxycycline?

If your dog misses a dose of doxycycline, give the missed dose as soon as you remember. If it is close to the time of your dog’s next dose, skip the missed dose. Then, continue to give your dog doxycycline on their regular medication schedule. Do not double up on doxycycline doses.