Dangerous foods
Some foods consumed safely by humans are harmful to dogs:
Chocolates
Chocolate contains theobromine, a chemical stimulant
that, together with caffeine and theophylline, belongs to the group of
methylxanthine alkaloids. Dogs are unable to metabolize theobromine
effectively. If they eat chocolate, the theobromine can remain in their
bloodstreams for days, and dogs may experience fast heart rate, severe
diarrhea, epileptic seizures, heart attacks, internal bleeding, and eventually
death. "One ounce of milk chocolate per pound of body weight is a
potentially lethal dose in dogs."In case of accidental intake of chocolate
by especially a smaller dog, contact a veterinarian or animal poison control
immediately; it is commonly recommended to induce vomiting within two hours of
ingestion. If chocolate ingestion is suspected (mostly dark or baking
chocolate), hydrogen peroxide can be used to safely induce vomiting, then
making a trip to the veterinarian is suggested. Large breeds are less
susceptible to chocolate poisoning, but can still die after eating four ounces
of chocolate.
Note:Carob
treats are often available as dog treats; these are unrelated to chocolate and
are safe.
Grapes and raisins
Grapes and raisins can cause acute kidney failure in dogs
(see also grape and raisin toxicity in dogs). The exact mechanism is not known,
nor is there any means to determine the susceptibility of an individual dog.
While as little as one raisin can be toxic to a susceptible ten pound dog, some
other dogs have eaten as much as a pound of grapes or raisins at a time without
ill effects. The affected dog usually vomits a few hours after consumption and
begins showing signs of renal failure three to five days later. A mycotoxin is
suspected to be involved, but one has not been found in grapes or raisins
ingested by affected dogs.
Onions
Onions cause hemolytic anemia in dogs (and cats). Allyl
propyl disulfide has been reported as being considered to be the main cause of
onion poisoning in dogs. Thiosulfate has also been reported as being
implicated. Thiosulfate levels are not affected by cooking or processing.
Occasional exposure to small amounts is usually not a problem, but continuous
exposure to even small amounts can be a serious threat. Also garlic contains
thiosulfate, even if to a significantly lesser extent, and it is also known to
cause diarrhea and vomiting.
Macadamia nuts
Macadamia nuts can cause non-fatal stiffness, tremors,
hyperthermia, and abdominal pain. The exact mechanism is not known. Most dogs
recover with supportive care when the source of exposure is removed.
Hops
Hops, a plant used in making beer, can cause malignant
hyperthermia in dogs, usually with fatal results. Certain breeds, such as
Greyhounds, seem particularly sensitive to hop toxicity, but hops should be
kept away from all dogs. Even small amounts of hops can trigger a potentially
deadly reaction, even if the hops are "spent" after use in brewing.
Yeast
Yeast dough poses two risks. One, intestinal obstruction.
Two, the yeast can ferment internally resulting in ethanol (alcohol) poisoning.
Xylitol
Xylitol is a sugar substitute used in chewing gum,
chewable vitamins, candy, toothpaste, and other products. Although empirical
studies indicate xylitol may be safe for dogs, there have been cases of foods,
candies and gums containing xylitol causing toxic or even fatal liver damage in
dogs and should be avoided.