Project Description

If you have any reason to suspect your pet has ingested something toxic, please contact your veterinarian or one of the other resources listed:
ASPCA Animal Poison Control Center 24-hour hotline at (888) 426-4435
• Pet Poison Helpline® 24-hour animal poison control service at (855) 764-7661


Generic Name: diltiazem
Brand Names: Cardiazem, Cardiazem CD, Cartia XT, Dilacor XR, Tiazac, Dilt-CD, Dilt-XR, Diltia XT

Diltiazem, a calcium channel blocker, is commonly used in human and veterinary medicine to treat many disease states including various cardiac diseases and renal complications. Despite its use in animals, accidental overdose of diltiazem can be dangerous for pets.


Please note that other calcium channel blockers (such as amlodipine, verapamil, nefedipine, and felodipine) carry similar toxicity risks.

Signs and symptoms of toxicity: Signs of toxicity include vomiting, decreased heart rate, low blood pressure, altered mental status, diarrhea and weakness.

Toxic consumption:
In dogs, doses of 50 mg/kg may cause intoxication. There is no established toxic threshold for cats. All incidents of accidental exposure should be reported immediately.

Dogs: Diltiazem Toxic Consumption
Yorkie, Chihuahua
Pug, Boston Terrier, Poodle
Beagle, Scottish Terrier
Boxer, Cocker Spaniel
Labrador & Golden Retrievers, German Shepherd
Great Dane, St. Bernard
1 – 10 lbs.
(0.45 – 4.6 kg)
11 – 25 lbs.
(5 – 11.4 kg)
26 – 40 lbs.
(11.8 – 18.2 kg)
41 – 70 lbs.
(18.6 – 31.8 kg)
71 – 90 lbs.
(32.3 – 40.9 kg)
91 – 110 lbs.
(41.4 – 50 kg)
dog1 dog2 dog3 dog4 dog7 dog6
> 22 mg > 249 mg > 589 mg > 929 mg > 1614 mg > 2069 mg


– Costello M, Syring RS. Calcium channel blocker toxicity. J Vet Emerg Crit Care 2008; 18:54-60.
– Osweiler, G, et al. (2011). Blackwell’s five-minute veterinary consult clinical companion. Small Animal Toxicology. [Kindle version]. Retrieved from

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