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Side Effects of Frontline for Fleas & Ticks

| Updated September 26, 2017

Frontline Plus Flea and Tick Control is one of the most commonly prescribed medications for pets. Fipronil and methoprene are the main active ingredients in Frontline. Combined, these parasiticides kill fleas before they bite as well as kill ticks that may spread serious bacterial diseases. Although this is one of the most effective conventional flea and tick medications, it does come with some potential side effects. After applying Frontline Plus Flea and Tick Control, note if the pet exhibits any symptoms that may require veterinarian intervention.

Skin Irritation

Skin irritation, redness and sensitivity at the application site are one of the most prevalent side effects of Frontline Plus Flea and Tick Control. This is not a serious side effect. However, some animals may try to scratch at the application site until the medicine penetrates the skin. This often spreads the medicine to other areas of the body, potentially even the face and eye area. If a pet has developed a rash, swelling or has gotten medication in the eyes, seek veterinary assistance.

Appetite Loss

It is not uncommon for animals to try and lick the irritated application spot. Although it is not possible for them to actually get at the application spot, it is possible that an animal may accidentally ingest some of the medicine. This will cause a loss of appetite as well as an upset stomach. Ensure that the pet has extra water to help relieve these effects.

Excess Salivation and Drooling

According to PetDrugs.com, dogs who have licked or ingested Frontline Plus Flea and Tick Control will experience excess salivation and often uncontrollable drooling. Avoid excess salivation and drooling by putting the topical medication above the shoulder blades in a spot that the animal cannot reach. It is prudent to watch the pet for 24 hours while the medication is absorbed to prevent the pet from rubbing or smearing the medication.

Reversible Neurological and Psychological Effects

PetDrugs.com asserts that Frontline Plus Flea and Tick Control and other canine drugs that contain fipronil often cause depression, sensitivity to increased or abundant stimulation, as well as general feelings of apprehension and nervousness. These symptoms often go away once the animal is no longer exposed to the drug.

Vomiting and Diarrhea

If a dog exhibits severe side affects such as vomiting and diarrhea, the animal might have overdosed on the medicine. These symptoms, along with aggression, respiratory problems, seizures and trembling, indicate that the animal is in distress and should be treated immediately.