Cocoa Mulch Toxicity in Dogs

Cocoa mulch is made from cocoa beans shells from the Theobroma cacao plant. These bean shells are a by-product of chocolate production and are popular for home landscaping. While many dogs are attracted to the chocolate smell of the mulch, the shells do contain theobromine and caffeine. These are methylxanthine alkaloids that dogs are sensitive to, and ingestion can cause methylxanthine toxicosis. The severity of the symptoms will depend on the amount ingested. Toxicity can occur at a dose of 100-250 mg, meaning a 60 lb. dog only needs to eat less than 3 ounces of cocoa mulch to become poisoned.

Cocoa mulch toxicity can occur in dogs when cocoa mulch has been ingested. Related to chocolate, cocoa mulch poisoning can exhibit the same symptoms of vomiting, diarrhea, and seizures. While not usually fatal if treated, death can occur if large quantities are ingested, often in 12 to 48 hours. Seek medical treatment immediately for this emergency if you suspect your dog may be poisoned.

Symptoms of cocoa mulch poisoning can be similar to those of chocolate ingestion. They usually begin within 2 to 4 hours after ingestion and can last up to 36 hours. While small quantities can cause gastrointestinal issues, other more serious symptoms from larger doses can include:

• Vomiting
• Diarrhea
• Muscle tremors
• Rapid heart rate
• Irregular heart rate
• Increase in blood pressure
• Hyperactivity or nervousness
• GI complications
• Blood in the urine
• Frequent urination
• Increase in body temperature
• Muscle rigidity
• Dilated pupils
• Rapid breathing
• Increased thirst
• Overactive responses
• Seizures

The main cause of methylxanthine toxicosis is the ingestion of theobromine and caffeine. Unprocessed cocoa beans contain 1% to 4% theobromine and 0.07% to 0.36% caffeine, but processed cocoa bean shells that are present in cocoa mulch can contain up to 2.98% theobromine. 

While all dogs are at risk as long as cocoa mulch is within reach, there are special risks for these dogs:

• Pregnant dogs have a higher risk of abnormal fetus development or newborn birth defects
• Nursing dogs have a higher risk of nervous system overstimulation

If you suspect your dog has ingested cocoa mulch, try to avoid stress or overexcitement, as they can make symptoms worse that are related to the nervous system, such as overactive responses and seizures. Seek medical attention immediately, as recovery can be dependent on how soon treatment can begin.

Tell your veterinarian as much as you know about the ingestion, such as when it occurred and how much was ingested. A complete exam, previous medical history, time since ingestion, symptoms present, and weight of your dog will lead to a diagnosis and treatment plan. Often, treatment is initiated immediately. Tests may include blood tests, a urinalysis, and EKGs to help determine the severity of poisoning, as well as organ function and heart rate.

Treatment has a better success rate if it is started within 1-4 hours after ingestion. Recovery is good if some or all of the toxic material is removed within that time. If your dog develops more serious symptoms, such as seizures and cardiac issues, prognosis is guarded.

First, your veterinarian will try to remove the toxic material by inducing vomiting if your dog is not having seizures. An emetic drug is often administered, such as hydrogen peroxide, ipecac or apomorphine. Then, the stomach may be flushed with fluids. Your dog may also be fed activated charcoal every 4 to 6 hours to prevent further absorption by binding the toxin in the stomach.

Next, supportive therapy includes an IV to administer fluid therapy and promote hydration. This also increases the rate of toxin excretion and provide supplementation for electrolytes lost during vomiting. Drugs to help with tremors, hyperactivity, seizures, and rapid, abnormal or slow heart rates can also be administered. 

A catheter may be placed to remove urine from the bladder. This can reduce any reabsorption of the methylxanthines back into the body. An EKG may be used to monitor heart rate and evaluate recovery. After recovery, your dog may be kept to monitor for signs of cardiovascular issues, and mild to moderate kidney disease.

Successful treatment leads to a quick recovery. Your veterinarian may prescribe a bland diet to recover from any gastrointestinal issues for several days. Prevent your dog from becoming poisoned by cocoa mulch by refraining from using it on your property, and avoid contact with it in other places if possible.