Indian Hemp Poisoning in Dogs

Indian hemp is a perennial herb that can grow up to six feet tall, has red stems and simple green leaves which contain a milky sap that can cause dermal irritation to exposed skin and eyes. This is due to the cardenolide cardiac glycosides apocynin and apocynamarin in the sap. The flowers are clumps of small, bell-shaped sweet-smelling white and pink blooms. These flowers produce small pods filled with hundreds of seeds tipped with a hair-like cotton material to help them disperse. These are found all over the United States and Canada in wooded areas, fields, roadsides, and along waterways. The root contains another cardiac glycoside, cymarin, which can be lethal even in small doses.

Indian hemp (Apocynum cannabinum) is known to be toxic to dogs if ingested. In fact, the name apocynum actually means “away dog” in Greek. Even though it has a foul and bitter taste, just chewing on a leaf and not swallowing it can be dangerous for your dog. There are several toxic properties in Indian hemp, which are apocynamarin, apocynin, and cymarin, which are all cardenolide cardiac glycosides. Each one of these can affect the skin (contact dermatitis), cardiotonic system (heart muscle contractions), renal and hepatic (kidney and liver) functions, and the gastrointestinal tract (diarrhea, vomiting). The entire plant is poisonous, but the new plants (shoots) and roots have the highest concentration of toxins.

Even though it has a foul and bitter taste, just chewing on a leaf and not swallowing it can be dangerous for your dog. There are several toxic properties in Indian hemp, which are apocynamarin, apocynin, and cymarin, which are all cardenolide cardiac glycosides. Each one of these can affect the skin (contact dermatitis), cardiotonic system (heart muscle contractions), renal and hepatic (kidney and liver) functions, and the gastrointestinal tract (diarrhea, vomiting). The entire plant is poisonous, but the new plants (shoots) and roots have the highest concentration of toxins.

Some signs that your dog may be suffering from Indian hemp poisoning are:

• Contact dermatitis (red rash, itching, painful inflammation)
• Dilated pupils
• Unusually excessive drooling
• Nausea
• Pale mucous membranes
• Cold paws
• Increased temperature
• Appetite loss
• Vomiting
• Weakness
• Tremors
• Abnormal heartbeat (too fast, too slow, irregular, weak)
• Seizures
• Collapse
• Death

 Types

Indian hemp, or apocynum cannabinum, is part of the apocynaceae family and is found all over the United States and Canada. Some of the most common names for Indian hemp are:

• Amy root
• Dogbane
• Hemp dogbane
• Prairie dogbane
• Rheumatism root
• Wild cotton

The causes of Indian hemp poisoning are several cardiac glycoside cardenolides:

• Apocynamarin in the whole plant
• Apocynin in the whole plant
• Cymarin in the root

The best way to get a definitive diagnosis of Indian hemp poisoning is to bring a sample of the plant to show the veterinarian or take a photograph with your cell phone. This will help your veterinarian decide on a treatment plan for your pet. It can also help if you bring your dog’s medical records and be sure to tell the veterinarian if your pet is on any medications or has had any recent illnesses.

Next, a complete physical examination will be done to determine your pet’s overall condition. This includes assessing your dog’s coat and skin condition, body weight, temperature, reflexes, pulse, oxygen levels, breath sounds, and blood pressure. To check your dog’s airway for swelling and inflammation, an endoscopy will be done using a long, flexible tube with a camera on the tip. This procedure is usually done while your pet is sedated to prevent additional stress and anxiety. Abdominal radiographs (x-rays) are also needed to make sure there are no blockages or inflammation in your pet’s intestinal tract. If the veterinarian needs a more detailed view, an ultrasound, MRI, or CT scan may be performed as well. An electrocardiogram (EKG) is usually done to monitor the electrical and muscular functions of your dog’s heart.

Additionally, the veterinarian will want to do some laboratory tests, such as a urinalysis, fecal examination, packed cell volume (PCV), liver enzyme panel, biochemical profile, metabolic panel, blood urea nitrogen (BUN), and complete blood count.

Indian Hemp poisoning is treated similarly to other poisoning conditions with evacuation, detoxification, fluid therapy, medication, and observation (usually in the hospital). Of course, the specific treatment will vary depending on the condition and age of your dog as well as the amount of Indian hemp that was consumed.

Evacuation

Emesis (vomiting) will be instigated by giving oral peroxide solution or ipecac. In addition, activated charcoal will be given by mouth to absorb any plant particles or sap that have not been digested yet. This step may be repeated depending on the amount of Indian hemp your dog ate.

Detoxification

A gastric lavage is sometimes performed if the veterinarian believes there is still undigested plant particles or toxic substances in your dog’s system. While your dog is sedated, a flexible hose called an orogastric tube will be inserted through your dog’s mouth into the stomach. Warm saline is then pumped gently into the stomach and allowed to flow out into a bucket, rinsing away the toxins.

Fluid Therapy

To flush the kidneys and prevent dehydration, fluids will be given by intravenous (IV) line. This may be continued for several hours, depending on the amount of Indian hemp your dog ate.

Medication

To reverse the cardiac effects, the veterinarian will give propranolol and possibly phentolamine or atropine. To settle the gastric distress, a stomach protectant and antacid may help. If needed, oxygen therapy will be given.

Observation

If your dog is showing signs of improvement, the veterinarian will probably send you home after a few hours. However, if a large amount of Indian hemp was eaten, an overnight stay in the hospital for observation may be recommended.

Indian hemp poisoning recovery depends on the amount eaten and how fast you were able to get medical treatment. In most cases, if you are able to get treatment within the first six hours, prognosis is good. Be prepared to watch your dog for several days and if there are any complications, give your veterinarian a call.