Giving kittens dewormer is an important part of their health care, especially when they are young. Deworming helps get rid of intestinal parasites like roundworms, hookworms, and tapeworms that can make kittens very sick. But some pet owners wonder if it’s possible to give too much dewormer to kittens and cause harm.
How dewormers work
Dewormers are medications that are designed to either kill intestinal worms or paralyze them so they detach from the intestinal lining and get expelled from the body. Some common deworming medications for cats include:
- Pyrantel pamoate (common brand name Nemex)
- Fenbendazole (common brand name Panacur)
- Praziquantel (common brand name Droncit)
- Ivermectin (common brand name Heartgard)
- Milbemycin oxime (common brand name Interceptor)
These medications have a wide margin of safety, meaning an animal would need to ingest a very large overdose to cause significant adverse effects. The doses in dewormers are formulated to be effective at getting rid of worms while remaining very safe.
Deworming schedule for kittens
Veterinarians typically recommend deworming kittens:
- Starting at 2-3 weeks of age
- Every 2 weeks until 3 months of age
- Then monthly until 6 months of age
Frequent deworming when kittens are very young helps eliminate worms they may have gotten from their mother in utero or from nursing. By 6 months of age, their immune systems are stronger and they are not as susceptible to reinfection.
Can you give too much dewormer?
Giving too much dewormer can potentially cause toxicity, but the doses would have to be exceedingly high. Some possible effects of dewormer toxicity include:
- Vomiting
- Diarrhea
- Low energy/lethargy
- Incoordination/unsteadiness
- Tremors
- Seizures (rarely)
Signs of toxicity could occur within hours of an overdose. In most cases, side effects are mild and resolve on their own as the medication is metabolized and expelled from the body.
Risk factors for toxicity
Very young kittens are at higher risk of toxicity if too much dewormer is given because their bodies cannot metabolize medications as efficiently. Kittens less than 2 weeks old should not be dewormed unless specifically advised by a veterinarian, as their immature livers cannot break down the medication well.
Also at increased risk are kittens who are sick or debilitated. Health issues like liver or kidney disease can decrease a kitten’s ability to metabolize certain dewormers.
Giving the proper dose
When giving your kitten dewormer, always follow label instructions carefully. Do not exceed the recommended dose for your kitten’s age and weight. Here are some tips for safe dewormer administration:
- Weigh your kitten accurately before dosing. Do not guess the weight.
- Calculate the proper dose based on kitten’s weight.
- Use a syringe or dosing spoon to measure out the correct amount.
- Do not split or share doses between multiple kittens.
- Read and follow label directions closely.
- Do not double up or give extra doses.
Using the deworming products as labeled and prescribed will provide the benefits of eliminating intestinal parasites while remaining safe and non-toxic.
Signs of dewormer toxicity
If your kitten shows any concerning signs after being dewormed, take note of the symptoms. Here are some signs that may indicate possible dewormer toxicity:
- Vomiting – Usually occurs within 6 hours of an overdose. Look for multiple episodes of vomiting or throwing up undigested food.
- Diarrhea – Profuse, watery stool can start within 6-12 hours of an overdose.
- Lethargy – Being very quiet, excessively sleeping, loss of normal energy level.
- Loss of coordination – Wobbly movements, difficulty walking or standing, falling over.
- Tremors/seizures – Involuntary muscle twitching or rigidity of the body, jerking movements, convulsions. Rare with dewormer toxicity.
Cats tend to hide illness very well, so any obvious signs of toxicity should be addressed promptly. Take note if symptoms occur shortly after deworming.
When to seek emergency care
In most cases of possible dewormer overdose, the effects are mild. But seek emergency vet care right away if your kitten shows:
- Repeated vomiting or diarrhea lasting more than 24 hours
- No interest in food or water for more than 12 hours
- Severe lethargy, unable to stand or function normally
- Seizures
These signs can progress to very serious conditions like dehydration, shock, or liver damage if left untreated. Emergency vet care can provide IV fluids, medications, and supportive care to stabilize your kitten.
Diagnosing dewormer toxicity
If you take your kitten to the vet with possible dewormer toxicity, the vet will ask about:
- Recent deworming history – what medication was given, at what dose, and when
- Onset of clinical signs – when symptoms first appeared
- Vaccination history
- Other medications/supplements
- General health status
Your vet will thoroughly examine your kitten and look for symptoms consistent with dewormer toxicity like vomiting, diarrhea, lethargy, tremors, etc. They may recommend bloodwork to check liver and kidney function for any abnormalities.
Most cases of toxicity can be diagnosed based on clinical signs and history. Treatment is then aimed at providing supportive care while the medication works its way out of the kitten’s system.
Treating dewormer toxicity
There is no antidote to reverse dewormer toxicity. Treatment focuses on providing supportive care, which may include:
- IV fluids – Correct dehydration and maintain normal fluid levels.
- Anti-vomiting medication – Reduce nausea and vomiting.
- Gastroprotectants – Help heal stomach/intestinal irritation.
- Monitoring – Frequent veterinary exams to watch for improving symptoms.
- Hospitalization – In severe cases, around-the-clock monitoring and care.
Most kittens respond very well to this type of supportive therapy. They are observed until clinical signs resolve, which may take 24-48 hours in mild toxicity cases or a few days in more severe cases.
Outcomes for mild toxicity
With mild dewormer toxicity, most kittens make a full recovery within a day or two of starting treatment, once the medication has passed through their system. The prognosis is good, with no long-lasting effects.
Outcomes for severe toxicity
In cases of severe toxicity with serious clinical signs, the prognosis becomes more guarded. However, fatal toxicity is very rare and most kittens will recover with aggressive therapy. Kidney or liver damage can sometimes occur, which may need ongoing monitoring and care.
Preventing dewormer toxicity
You can help prevent toxicity by following these safe deworming practices:
- Carefully follow your vet’s prescribed deworming schedule and doses.
- Never give extra doses or combine medications unless directed.
- Using a syringe, carefully measure doses based on kitten’s weight.
- Supervise dosing to ensure the full amount is consumed.
- Never split medication between kittens or reuse syringes.
- Store dewormer safely out of kitten’s reach.
- Watch for any vomiting/diarrhea after deworming.
With attentive, responsible dosing according to your vet’s recommendations, dewormers are very safe and effective medications for your kitten.
Risk vs benefit of deworming kittens
There’s no doubt that intestinal worms pose a significant health risk to kittens. Worms compete for nutrients, cause intestinal blockages, and allow deadly translocation of bacteria. Kittens can become malnourished, dehydrated, or septicemic when worms are left untreated.
Deworming carries a very small risk of toxicity, with mild symptoms at appropriate doses. The benefits clearly outweigh potential risks when used properly under veterinary guidance.
| Risk | Benefit |
|---|---|
| Mild vomiting or diarrhea in some cats | Elimination of worm infestation |
| Rare chance of severe toxicity if massive overdose given | Improved nutrient absorption and growth |
| Potential for inadequate dosing if shared between littermates | Prevention of intestinal obstructions |
Overall the well-established safety record and proven efficacy of modern dewormers makes the small risks worthwhile to protect kittens’ health.
Can deworming cause other health issues later on?
There is no scientific evidence showing that appropriately dosed deworming causes any long-term health issues later in a cat’s life when given according to veterinary guidelines as a kitten. Some people worry that “overvaccinating” kittens can cause problems like vaccine-associated sarcomas later on. But dewormers work very differently than vaccines, and act locally in the intestinal tract rather than stimulating the immune system. They are quickly metabolized and excreted from the body within 24 hours.
Some effects that may be anecdotally associated with kitten deworming include:
- Coat color changes – Normal variations as kittens mature.
- Behavior changes – Normal as kittens develop.
- Picky eating – Common in adolescent kittens.
- Vomiting/diarrhea – Transitory effects of medication.
- Lethargy – Usually stress/travel related.
There are no scientifically documented connections between routine kitten deworming protocols and chronic health conditions later in life. Discuss any concerns with your veterinarian.
Why lifelong immunity doesn’t develop
Deworming medications work by directly killing worms or paralyzing them, not by stimulating the body’s immune defenses. So they don’t provide any lasting immunity against future infections. Kittens build natural immunity over time as their bodies learn to resist and expel worms. But protection is never complete, so dogs and cats remain susceptible to reinfection throughout life.
Conclusion
Giving kittens dewormer according to your veterinarian’s prescribed schedule and dosages is vital to protecting their health, especially in the first few months of life. While it’s theoretically possible to cause toxicity if many times the recommended dose were given, this scenario rarely happens with responsible medication administration. The well-established safety record of dewormers makes their use far safer than allowing intestinal worms to infect and damage a kitten’s digestive tract. Deworming according to veterinary protocols is an extremely important component of kitten healthcare with benefits that far outweigh the negligible risks.
