Theobromine poisoning, also informally called chocolate poisoning or cocoa poisoning, is an overdosage reaction to the
xanthine
Xanthine ( or ; archaically xanthic acid; systematic name 3,7-dihydropurine-2,6-dione) is a purine base found in most human body tissues and fluids, as well as in other organisms. Several stimulants are derived from xanthine, including caffein ...
alkaloid
Alkaloids are a class of basic, naturally occurring organic compounds that contain at least one nitrogen atom. This group also includes some related compounds with neutral and even weakly acidic properties. Some synthetic compounds of simila ...
theobromine
Theobromine, also known as xantheose, is the principal alkaloid of '' Theobroma cacao'' (cacao plant). Theobromine is slightly water- soluble (330 mg/L) with a bitter taste. In industry, theobromine is used as an additive and precursor to ...
, found in
chocolate
Chocolate is a food made from roasted and ground cacao seed kernels that is available as a liquid, solid, or paste, either on its own or as a flavoring agent in other foods. Cacao has been consumed in some form since at least the Olmec ci ...
,
tea,
cola
Cola is a carbonated soft drink flavored with vanilla, cinnamon, citrus oils and other flavorings. Cola became popular worldwide after the American pharmacist John Stith Pemberton invented Coca-Cola, a trademarked brand, in 1886, which was imi ...
beverages,
and some other foods.
Sources
Cocoa powder
Cocoa may refer to:
Chocolate
* Chocolate
* '' Theobroma cacao'', the cocoa tree
* Cocoa bean, seed of ''Theobroma cacao''
* Chocolate liquor, or cocoa liquor, pure, liquid chocolate extracted from the cocoa bean, including both cocoa butter an ...
contains about theobromine by
weight
In science and engineering, the weight of an object is the force acting on the object due to gravity.
Some standard textbooks define weight as a vector quantity, the gravitational force acting on the object. Others define weight as a scalar qua ...
, so of raw cocoa contains approximately theobromine.
Processed chocolate, in general, has smaller amounts. The amount found in highly refined chocolate candies or sweets (typically ) is much lower than that of
dark chocolate or unsweetened
Baker's Chocolate
Baker's Chocolate is a brand name for the line of baking chocolates owned by Kraft Heinz. Products include a variety of bulk chocolates, including white and unsweetened, and sweetened coconut flakes. It is one of the largest national brands of ch ...
( or ).
In species
Humans
Pharmacology
Theobromine has a half-life of , but over may be unmodified after a single dose of
In general, the amount of theobromine found in chocolate is small enough that chocolate can be safely consumed by
human
Humans (''Homo sapiens'') are the most abundant and widespread species of primate, characterized by bipedalism and exceptional cognitive skills due to a large and complex brain. This has enabled the development of advanced tools, cultu ...
s with a negligible risk of poisoning.
Toxicity
Theobromine doses at per day, such as may be found in of cocoa powder may be accompanied by sweating, trembling and severe
headaches
Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches.
Headaches can occur as a resu ...
. These are the mild-to-moderate symptoms.
The severe symptoms are cardiac
arrhythmias
Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adults ...
,
epileptic seizures
An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much of the body with los ...
,
internal bleeding
Internal bleeding (also called internal hemorrhage) is a loss of blood from a blood vessel that collects inside the body. Internal bleeding is usually not visible from the outside. It is a serious medical emergency but the extent of severity dep ...
,
heart attacks
A myocardial infarction (MI), commonly known as a heart attack, occurs when blood flow decreases or stops to the coronary artery of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may ...
, and eventually
death
Death is the irreversible cessation of all biological functions that sustain an organism. For organisms with a brain, death can also be defined as the irreversible cessation of functioning of the whole brain, including brainstem, and brain ...
.
Limited mood effects were shown at per day.
In other species
Toxicity
Median lethal () doses of theobromine have only been published for cats, dogs, rats, and mice; these differ by a factor of 6 across species.
Serious poisoning happens more frequently in domestic animals, which
metabolize theobromine much more slowly than humans, and can easily consume enough chocolate to cause poisoning. The most common victims of theobromine poisoning are
dogs,
for whom it can be fatal. The toxic dose for
cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...
s is even lower than for dogs.
However, cats are less prone to eating chocolate since they are
unable to taste sweetness. Theobromine is less toxic to rats and mice, who all have an of about .
In dogs, the
biological half-life
Biological half-life (also known as elimination half-life, pharmacologic half-life) is the time taken for concentration of a biological substance (such as a medication) to decrease from its maximum concentration ( Cmax) to half of Cmax in the bl ...
of theobromine is 17.5 hours; in severe cases, clinical symptoms of theobromine poisoning can persist for 72 hours. Medical treatment performed by a
veterinarian
A veterinarian (vet), also known as a veterinary surgeon or veterinary physician, is a medical professional who practices veterinary medicine. They manage a wide range of health conditions and injuries in non-human animals. Along with this, vet ...
involves inducing
vomiting
Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose.
Vomiting can be the result of ailments like food poisoning, gastroenter ...
within two hours of ingestion and administration of
benzodiazepine
Benzodiazepines (BZD, BDZ, BZs), sometimes called "benzos", are a class of depressant drugs whose core chemical structure is the fusion of a benzene ring and a diazepine ring. They are prescribed to treat conditions such as anxiety disorders, ...
s or
barbiturate
Barbiturates are a class of depressant drugs that are chemically derived from barbituric acid. They are effective when used medically as anxiolytics, hypnotics, and anticonvulsants, but have physical and psychological addiction potential a ...
s for seizures,
antiarrhythmic
Antiarrhythmic agents, also known as cardiac dysrhythmia medications, are a group of pharmaceuticals that are used to suppress abnormally fast rhythms (Tachycardia, tachycardias), such as atrial fibrillation, supraventricular tachycardia and vent ...
s for
heart arrhythmia
Arrhythmias, also known as cardiac arrhythmias, heart arrhythmias, or dysrhythmias, are irregularities in the heartbeat, including when it is too fast or too slow. A resting heart rate that is too fast – above 100 beats per minute in adult ...
s, and
fluid diuresis. Theobromine is also suspected to induce
right atrial cardiomyopathy after long term exposure at levels equivalent to approximately of dark chocolate per day. According to the
Merck Veterinary Manual
The ''Merck Veterinary Manual'' is a reference manual of animal health care. It was first published by Merck & Co., Inc. in 1955. It contains concise, thorough information on the diagnosis and treatment of disease in a wide variety of species. ...
, Baker's Chocolate of approximately of a dog's body weight is sufficient to cause symptoms of toxicity.
For example, of Baker's Chocolate would be enough to produce mild symptoms in a dog, while a 25% cacao chocolate bar (like milk chocolate) would be only 25% as toxic as the same dose of Baker's Chocolate.
One ounce of milk chocolate per pound of body weight is a potentially lethal dose in dogs.
Wildlife
In 2014, four
American black bear
The American black bear (''Ursus americanus''), also called simply a black bear or sometimes a baribal, is a medium-sized bear endemic to North America. It is the continent's smallest and most widely distributed bear species. American black bear ...
s were found dead at a bait site in
New Hampshire
New Hampshire is a U.S. state, state in the New England region of the northeastern United States. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Gulf of Maine to the east, and the Canadian province of Quebec t ...
. A
necropsy
An autopsy (post-mortem examination, obduction, necropsy, or autopsia cadaverum) is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode, and manner of death or to evaluate any di ...
and
toxicology
Toxicology is a scientific discipline, overlapping with biology, chemistry, pharmacology, and medicine, that involves the study of the adverse effects of chemical substances on living organisms and the practice of diagnosing and treating e ...
report performed at the
University of New Hampshire
The University of New Hampshire (UNH) is a public land-grant research university with its main campus in Durham, New Hampshire. It was founded and incorporated in 1866 as a land grant college in Hanover in connection with Dartmouth College ...
in 2015 confirmed they died of
heart failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome, a group of signs and symptoms caused by an impairment of the heart's blood pumping function. Symptoms typically include shortness of breath, excessive fatigue, ...
caused by theobromine after they consumed of chocolate and doughnuts placed at the site as bait. A similar incident killed a black bear cub in
Michigan
Michigan () is a state in the Great Lakes region of the upper Midwestern United States. With a population of nearly 10.12 million and an area of nearly , Michigan is the 10th-largest state by population, the 11th-largest by area, and t ...
in 2011.
Pest control
In previous research, the
USDA
The United States Department of Agriculture (USDA) is the federal executive department responsible for developing and executing federal laws related to farming, forestry, rural economic development, and food. It aims to meet the needs of comme ...
investigated the possible use of theobromine as a toxicant to control
coyotes
The coyote (''Canis latrans'') is a species of canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological nich ...
preying on
livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to ani ...
.
See also
*
Xanthine oxidase
Xanthine oxidase (XO, sometimes XAO) is a form of xanthine oxidoreductase, a type of enzyme that generates reactive oxygen species. These enzymes catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthin ...
Footnotes
References
* (September 9, 2004)
* Merck Veterinary Manual (Toxicology/Food Hazards section), Merck & Co., Inc.,
Chocolate Poisoning'. (June 16, 2005)
External links
*
Toxicity basic facts
{{DEFAULTSORT:Theobromine Poisoning
Cat health
Dog health
Poisoning by drugs, medicaments and biological substances
Veterinary toxicology