Why one mothball is enough to trigger a crisis
A single mothball contains concentrated chemicals designed to vaporize slowly over months, which means your dog just ingested a full dose all at once. Even small dogs can absorb enough toxin from one mothball to overwhelm their liver's processing capacity within hours. The chemicals attack red blood cells first, reducing oxygen delivery to vital organs.
The timing matters here—if it happened within the last 30 minutes, the vet may still be able to prevent full absorption. But whether it's been minutes or hours, don't wait for symptoms like weakness or panting to appear. By then, internal damage is already progressing. Grab the mothball package or take a photo of its ingredients—this determines the treatment protocol.
How your dog's size changes the risk level
While all dogs are at risk, smaller breeds face faster toxin saturation. A 5kg Chihuahua absorbs proportionally more poison per pound than a 30kg Labrador from the same mothball. This doesn't mean large dogs are safe—their livers still struggle to break down these industrial-strength chemicals, just over a slightly longer timeframe.
Young puppies and senior dogs have additional vulnerabilities due to their less efficient metabolisms. If your dog falls into either category, or has any pre-existing liver conditions noted on past bloodwork, the situation escalates from urgent to critical. Emergency vets often prioritize these cases upon arrival.
The dangerous window before symptoms appear
Mothball poisoning has a deceptive latency period—your dog may seem fine for 1-4 hours before stumbling or acting disoriented. This isn't a sign of safety but of toxins circulating silently. The chemicals interfere with hemoglobin's oxygen-carrying capacity, creating a hidden crisis that suddenly manifests as collapse.
Watch for subtle early clues like faster-than-normal breathing or pale gums when you lift the lip. These indicate oxygen deprivation starting. Never assume that because your dog is still walking, the danger has passed. The damage compounds internally well before outward signs convince owners it's serious.
Why home treatment isn't an option here
Unlike some food toxins where monitoring at home might be advised, mothballs require professional intervention because their effects are both severe and irreversible without treatment. Activated charcoal—often used for other poisons—can't adequately bind these particular chemicals once they start circulating.
Veterinarians have specific protocols involving intravenous treatments to protect the liver and oxygen therapy to support compromised blood cells. They'll likely hospitalize your dog for 24-48 hours to monitor bloodwork trends. This isn't a case where "waiting it out" at home has a happy ending—the clock started ticking the moment the mothball was swallowed.
The step-by-step response, from the first minute to the vet visit, is in our Mothballs (Naphthalene, Paradichlorobenzene) emergency guide.