My dog ate chocolate: how much is actually toxic, by weight

How much chocolate is toxic to a dog?

The poison in chocolate is theobromine, a methylxanthine — the same chemical family as caffeine, which chocolate also contains in smaller amounts. Both stimulate the heart and the central nervous system, and the published thresholds are usually quoted for theobromine alone even though the caffeine fraction adds 10–20% to the real dose. People clear theobromine in roughly 6 to 10 hours (mean about 7). In dogs the elimination half-life is about 17.5 hours, and caffeine's is about 4.5 hours. A dog does not metabolise a chocolate dose so much as sit inside it: five half-lives is about 87 hours — three and a half days — before theobromine has substantially cleared.

Theobromine also undergoes enterohepatic recirculation: it is excreted in bile, reabsorbed from the intestine, and put back into circulation. It is reabsorbed across the bladder wall as well. This is why hospital treatment involves repeated doses of activated charcoal and a urinary catheter, and why a dog can look worse at hour ten than at hour two.

None of the numbers that matter are on the wrapper. What matters is milligrams of methylxanthine per kilogram of dog — the concentration of the chocolate, multiplied by the amount eaten, divided by the animal's body weight. A Labrador and a Chihuahua that eat the identical brownie have not had the identical exposure; they are two different cases with two different plans.

What is in each kind of chocolate

Reading the cocoa percentage off the wrapper

Theobromine tracks the cocoa solids, so the percentage printed on a dark bar is the single most useful thing on the label. It is usually on the front, as "70% cacao" or "70% cocoa solids". A 50% bar and an 85% bar differ by roughly two-fold, which is enough to move the same dog between two bands.

The four thresholds

These bands are what emergency clinicians use to decide whether a dog goes home with monitoring or onto a fluid line with an ECG. Signs typically begin 2 to 4 hours after ingestion, sometimes as late as 6 to 12, and can last 12 to 72 hours. A dog who looks completely normal 45 minutes after eating a bar has told you nothing at all.

The 20 to 40 mg/kg band is the one owners miss, because a dog with a heart rate of 190 at home just looks excited. The rhythm is where the damage shows, and the rhythm is not visible from across the room.

Worked example: a 20 lb dog and a bar of dark chocolate

Here is the arithmetic in full, the way our toxicology specialist runs it — a 20 lb terrier mix eats an entire 3.5 oz (100 g) bar of dark chocolate off the coffee table.

1. Convert the dog. 20 lb ÷ 2.2 = 9.1 kg.
2. Fix the amount eaten. The whole bar: 3.5 oz (100 g). Nothing left in the foil.
3. Pick the concentration. Start with a conservative 150 mg/oz — the low end for dark.
4. Total theobromine. 3.5 oz × 150 mg/oz = 525 mg.
5. Divide by the dog. 525 mg ÷ 9.1 kg = 58 mg/kg.
6. Read the band. 58 mg/kg sits at the top of the 40–60 mg/kg band: tremors, hyperthermia, severe agitation — two milligrams per kilo from the seizure threshold.

Now add the caffeine. Dark chocolate carries roughly 20 mg per ounce: 3.5 × 20 = 70 mg, or 7.7 mg/kg. The combined methylxanthine load is 595 mg — 65 mg/kg, over the seizure line rather than under it. And that was computed at 150 mg/oz. If the bar was a true 70–85% at ~225 mg/oz, theobromine alone is 787 mg, or 87 mg/kg, and with its caffeine about 94 mg/kg: well past the seizure threshold and close to the bottom of the reported lethal range of 100–200 mg/kg. This is a dog who needs to be seen now, not watched.

The same dog, a different snack. The 20 lb dog instead eats two squares off a milk chocolate bar — about 0.7 oz (20 g).

1. The dog is unchanged. 20 lb (9.1 kg).
2. Amount eaten. 0.7 oz (20 g).
3. Concentration. Milk chocolate, ~44 mg/oz theobromine and ~6 mg/oz caffeine.
4. Total methylxanthine. (0.7 × 44) + (0.7 × 6) = 31 + 4 = 35 mg.
5. Divide by the dog. 35 mg ÷ 9.1 kg = 3.8 mg/kg.
6. Read the band. Well under 20 mg/kg — below the level at which GI signs become likely, and nowhere near the cardiac one.

Same dog, same afternoon, same word — "chocolate" — and a 17-fold difference in dose: 65 mg/kg versus 3.8 mg/kg. One is an emergency room. The other is a dog who may vomit and may not. The number that goes wrong is almost never the chemistry; it is how much was actually eaten.

Chocolate toxicity chart: ounces per dog weight, by chocolate type

"He only ate a little" is the least reliable number in the calculation — it is an estimate made by someone who was not in the room. Weigh the packaging that is left, subtract it from the printed net weight, and assume the dog ate the difference. The dose that gets missed is the one that was estimated downward.

Symptoms of chocolate poisoning in dogs, in the order they appear

Signs arrive in stages, and which stage a dog reaches is set by the dose. Each group below is tagged with the band that produces it and the hours after eating when it typically shows.

1. Gastrointestinal — from about 20 mg/kg, usually 2–4 hours in. Vomiting (sometimes smelling of chocolate), diarrhoea, drooling, obvious thirst, frequent urination, restlessness or pacing that will not settle.
2. Cardiovascular — 20–40 mg/kg, usually 4–12 hours in. A fast or pounding heartbeat, heavy panting, wide eyes, hypertension, an irregular rhythm, a dog who cannot lie down.
3. Neuromuscular — 40–60 mg/kg, usually 4–12 hours in. Muscle tremors, stiffness, wobbliness or stumbling, severe agitation, a rising body temperature from the muscle activity itself.
4. Seizures and collapse — over 60 mg/kg. Convulsions, collapse, inability to stand. This is an immediate emergency at any hour.
5. Late complications — 12–72 hours in. Recurrent tremors or tachycardia as the drug recirculates; and, after a fatty chocolate meal, pancreatitis: repeated vomiting, a hunched posture, refusing food.

What happens next: the 72-hour timeline

Chocolate poisoning is slow, and that is the part almost nobody expects. A dog who ate a dark bar twenty minutes ago usually looks completely normal, and that normal-looking hour is exactly when treatment works best. Theobromine has to be absorbed before it can do anything, and once absorbed a dog eliminates it at a crawl — a half-life of roughly 17.5 hours, against about 6 to 10 hours in a person. The drug that arrives in the first few hours is still circulating a day and a half later.

Enterohepatic recirculation: why your dog can look better, then get worse

This is the fact most owners are never told, and it is the reason people leave a clinic early or decide at 3am not to go: chocolate poisoning gets better and then comes back.

Two mechanisms drive it. The first is enterohepatic recirculation: the liver dumps theobromine and its metabolites into bile, bile goes into the intestine, and the intestine absorbs the theobromine straight back into the bloodstream. The drug takes a lap and returns. The second is the bladder — theobromine filtered into urine is reabsorbed across the bladder wall, so urine sitting in a dog's bladder is a reservoir slowly feeding the poison back in. Both have a direct treatment answer: repeated activated charcoal for the gut loop, and a urinary catheter plus IV fluids for the bladder loop. That is why hospital treatment is not just "watching".

The sign owners discount most is the heart rate. A dog pacing and panting at hour six is not anxious about the vet — that is sinus tachycardia from methylxanthine stimulation, and at 20 to 40 mg/kg it can progress to ventricular premature complexes and runs of ventricular tachycardia. A resting rate over 140 in a medium-sized dog after a chocolate ingestion is a reason for an ECG.

What a veterinary team will do: emesis, activated charcoal, fluids, and heart monitoring

Chocolate has no antidote. Every step below aims at one of three things: get the undissolved dose out, stop the absorbed dose from recirculating, and support the heart and nervous system while the dog clears it. Knowing what each step is for makes it easier to consent to the right care — and to ask why, if something is skipped.

1. 1
   History and a dose calculation

   The treating clinic needs the dog's weight, the type of chocolate, the maximum amount that could have been eaten, and the time. From that they calculate milligrams per kilogram and place the dog in a risk band. This number determines everything that follows, which is why bringing the wrapper matters more than almost anything else you can do.
2. 2
   Inducing vomiting — only inside the window, only in the clinic

   If the dog is within roughly 1–2 hours of eating (sometimes longer for a large, fatty meal that empties slowly) and is alert with a normal gag reflex, the clinic will empty the stomach with an injectable emetic such as apomorphine. Recovered chocolate is dose that never has to be treated. Beyond that window, or in a dog already tremoring, seizing, or sedated, emesis is not attempted — the aspiration risk outweighs the yield.
3. 3
   Activated charcoal, often repeated

   Charcoal binds theobromine in the gut so it passes out in the stool instead of being absorbed. Because of enterohepatic recirculation one dose is frequently not enough: charcoal may be repeated every 4–6 hours for the first 24 hours to intercept each lap. Repeat doses are usually given without the cathartic (sorbitol) to avoid dehydration, and the treating clinic will watch sodium levels.
4. 4
   IV fluids

   Fluids correct dehydration from vomiting and diarrhoea, support blood pressure, and increase urine production so theobromine is flushed out rather than sitting in the bladder being reabsorbed.
5. 5
   A urinary catheter, or frequent walking

   Theobromine in urine crosses back through the bladder wall into the bloodstream. Keeping the bladder empty — an indwelling catheter in a hospitalised dog, or walking a less-affected dog to urinate very frequently — removes that reservoir. Together with repeated charcoal this reduces how much drug is recirculated; it does not shorten the 17.5-hour half-life, which is why monitoring still runs 24–72 hours.
6. 6
   ECG and blood pressure monitoring

   Continuous or intermittent ECG catches arrhythmias that a stethoscope and a heart-rate number miss: ventricular premature complexes, runs of ventricular tachycardia, and occasional early bradycardia. Blood pressure is tracked because methylxanthines drive hypertension.
7. 7
   A beta-1 selective blocker for a dangerous tachyarrhythmia

   If the heart rate stays high enough to compromise filling, or ventricular ectopy becomes significant, a short-acting beta-1 selective agent such as esmolol, or metoprolol, is used to slow conduction and control the rhythm. Non-selective agents such as propranolol are generally avoided in methylxanthine toxicosis because they reduce renal excretion of the drug you are trying to clear. These are given on the basis of an ECG, which is why the monitoring comes first.
8. 8
   Methocarbamol for tremors; a benzodiazepine for seizures

   Methocarbamol is a centrally acting muscle relaxant and the usual first choice for a tremoring dog, because tremors themselves generate dangerous heat. Seizures are controlled with diazepam or midazolam, sometimes with levetiracetam or a barbiturate if they recur. Body temperature is monitored throughout.
9. 9
   Bloodwork and pancreatitis follow-up

   Baseline chemistry and electrolytes, and — after a fatty ingestion — a check for lipaemia and pancreatitis in the days that follow, since that complication arrives after the theobromine has cleared.
10. 10
    Monitoring for as long as the drug lasts

    Given a 17.5-hour half-life, mild cases are commonly observed 12–24 hours and moderate-to-severe cases 24–72 hours. Discharge is based on a normal heart rhythm, no tremors, a stable temperature, and the dog eating — not on the clock alone.

An ER chocolate case is a monitoring case, not a five-minute one. The dogs that do badly arrive at hour ten already tremoring — by then there is nothing left in the stomach to remove and the whole dose is on board. A dog who reaches an emergency clinic inside the first hour, with the wrapper, is usually treated with an emetic, activated charcoal, fluids, and a night of ECG.

Why you must not decontaminate at home

Do not give hydrogen peroxide, salt, mustard, activated charcoal, or anything else unless a veterinarian is directing you on that specific call. This is an instruction about action, and here is exactly why it exists.

• 3% hydrogen peroxide causes real injury. It works by foaming and irritating the stomach lining, and that irritation is not always minor — documented cases include severe haemorrhagic gastritis, gastric ulceration, and oesophageal damage. Dogs have needed hospitalisation for the peroxide alone, after eating something that would not have hurt them.
• Aspiration is the worse outcome. A dog vomiting at home, unmonitored, can inhale stomach contents into the lungs. Aspiration pneumonia is far more dangerous than most chocolate doses, and a dog who is already agitated, tremoring, sedated, or seizing is at high risk of it — precisely the dog an owner most wants to make vomit.
• Salt is dangerous and has killed dogs. Salt given as an emetic causes hypernatraemia: brain cell dehydration, disorientation, seizures, and death. There is no dose of table salt that is a safe emetic. This one is a hard no.
• Activated charcoal is the right drug in the wrong hands. Syringing it into a nauseated or tremoring dog causes aspiration pneumonia, and the repeat dosing this poison needs can drive sodium to dangerous levels — which requires bloodwork to catch. Charcoal belongs with the emesis: in the clinic.
• Timing usually makes it pointless anyway. Past roughly two hours most of the theobromine has left the stomach. Vomiting then delivers all of the risk above and recovers almost none of the dose.
• Clinics have a better tool. Apomorphine by injection is reliable, fast, reversible, and given where aspiration can be managed. Many veterinary toxicologists now advise against at-home peroxide entirely, outside direct veterinary instruction.

Chocolate cases guides miss: edibles, cocoa powder, and what is inside the coating

Most chocolate pages stop at the calculator. But the calls that go badly are rarely a plain bar eaten in front of you at 8pm. They are the brownie from the top drawer, the box of chocolate-covered raisins, the keto bar, the advent calendar found shredded on the stairs at 6am. Every one of those changes the arithmetic — sometimes because a second toxin is in the room, sometimes because the chocolate is the least of it.

Cannabis edibles: the brownie that is two poisonings at once

A pot brownie or weed cookie is two toxins in one bite: theobromine plus THC, and the THC dose is usually nothing like a recreational human serving. THC is fat-soluble, so cannabutter concentrates it into the fat phase of the batter — a home batch made with an eighth or a quarter ounce of flower can put 30–80 mg of THC into a single brownie against a 5–10 mg human dose. Dogs show signs from roughly 0.5 mg/kg, so for a 20 lb (9 kg) dog under 5 mg is enough. One brownie can be a seven- to eighteen-fold overshoot.

The picture is distinctive and comes on faster than chocolate: 30–90 minutes, versus 2–4 hours for theobromine. Look for static ataxia — the dog stands rooted, swaying like a metronome, unable to walk straight but not collapsed; urine dribbling while standing or lying down; hyperesthesia, a violent startle to a dropped spoon; widely dilated pupils; a slow heart rate; and a low body temperature. Signs commonly run 18–24 hours and, with a concentrated edible, can stretch to 72 hours.

The dangerous part is that the two toxins mask each other. THC sedates and slows the heart; theobromine agitates and speeds it. A dog that looks flat, cold and sleepy can still be running a theobromine tachycardia underneath the sedation — which is why these cases get an ECG and blood pressure monitoring, not a quiet kennel and time. Care is supportive: IV fluids, warming, anti-emetics, repeated activated charcoal (both compounds recirculate through the gut), and in severe or non-responsive cases intravenous lipid emulsion, which pulls fat-soluble THC out of the tissues.

Static ataxia and urine dribbling in a dog that startles at sound are close to diagnostic for THC — that combination is not what theobromine does. The distinction matters because a chocolate-only dog gets treated for a fast heart, and a dog with both gets watched for a slow one.

Assume a homemade edible is stronger than a dispensary one. The dose is unlabelled, it is concentrated in butter, and the batch was portioned by eye.

Chocolate-covered raisins, espresso beans, and macadamias

In all three, the coating is the smaller problem. Raisins can cause acute kidney injury at doses nobody can predict — injury has been reported around 0.045 oz per pound of body weight (about 2.8 g/kg), which is roughly 0.9 oz (25 g) for a 20 lb (9 kg) dog, while other dogs eat a whole box with no measurable effect. There is no safe-dose line to sit under, so any raisin ingestion is treated as an exposure. Chocolate-covered espresso beans are a double methylxanthine hit: about 6 mg of caffeine in each bean, plus the theobromine in the chocolate coating around it. Twenty beans into a 20 lb (9 kg) dog is roughly 120 mg caffeine and about 100 mg theobromine from the coating — around 25 mg/kg combined, squarely in the cardiotoxic band, and caffeine hits harder and faster than theobromine. Plain roasted coffee beans or grounds carry very little theobromine and are a caffeine problem dosed differently. Macadamias produce hind-limb weakness, tremors and fever, usually within 12 hours; ten nuts is about 0.9 oz (25 g), roughly 2.8 g per kg for that same dog.

Sugar-free chocolate and xylitol

A sugar-free or keto chocolate bar can be more urgent than the chocolate in it. Xylitol — often labelled birch sugar — triggers a massive insulin release in dogs, and blood glucose can crash within 10 to 60 minutes, producing weakness, wobbliness, collapse or seizures. With gum and some slower-release products onset can be delayed 12 hours or more, so a normal dog at hour two is not cleared; glucose needs checking on a schedule a clinic sets. Around 0.1 g per kg is enough for hypoglycaemia — under 0.04 oz (1 gram) for a 20 lb (9 kg) dog. Above roughly 0.5 g per kg the risk becomes hepatic necrosis, which can appear 24–72 hours later, including in a dog whose blood glucose never dropped at all. Read the ingredient list, not the "sugar alcohol" line on the nutrition panel: erythritol and maltitol are not the same hazard, and a bar can contain both.

Xylitol changes the clock. Theobromine gives you a couple of hours before signs; xylitol can drop blood glucose inside thirty minutes, and the liver injury shows up two days after the dog looks recovered.

Cocoa mulch in the garden: the exposure with no wrapper

Cocoa bean shell mulch is a by-product of chocolate manufacture. It smells strongly of chocolate for weeks after it is laid, dogs find it irresistible, and published analyses put its theobromine anywhere from 0.19% to 2.98% by weight — roughly 54 to 845 mg per ounce, a 15-fold spread between brands and processing runs. That means a mulch dose can only be calculated as a range. A 30 lb (13.6 kg) dog that eats 2 oz (57 g) has taken in somewhere between about 110 mg and 1,690 mg — 8 mg/kg at the mild end, over 120 mg/kg at the worst, which spans everything from a soft stool to a seizure risk. You cannot tell which bag you bought by looking at the ground, so the high end is the assumption to work from. This is also the exposure owners never suspect, because there is no wrapper and no missing food: the dog simply starts vomiting in the garden. If cocoa mulch is on your property and your dog is unwell, tell the clinic it is there.

White chocolate: barely any theobromine, and still a reason to call

White chocolate holds about 0.25 mg of theobromine per ounce. To reach 40 mg/kg, a 20 lb (9 kg) dog would need roughly 1,440 oz — 90 lb (41 kg) of white chocolate. Methylxanthine poisoning is not what a white chocolate dose produces, and on that one number the calculator is unambiguous. The rest of it is not. A white chocolate bar is a concentrated bolus of fat and sugar, and a large one is a recognised trigger for pancreatitis: hunched posture, repeated vomiting, refusal of food and abdominal pain, usually appearing 12 hours to 3 days later rather than the same evening. Miniature Schnauzers, Yorkshire Terriers, overweight dogs and any dog with a prior episode sit at higher risk. Add the foil and the plastic tray and a "harmless" white chocolate raid can still end at the clinic.

With white chocolate the theobromine maths is reassuring and the fat is not. A large fatty bolus is a recognised pancreatitis trigger, especially in Schnauzers, Yorkies and any dog that has had an episode before — watch for a dog that will not settle, will not eat, and stands with its front end down.

Foil, wrappers, and the advent calendar problem

Small amounts of foil often pass in the stool, but that is not something to count on. Cupcake liners, plastic advent trays, Easter basket grass and whole unopened wrappers do not reliably pass, and in a small dog a wad of packaging can cause a gastrointestinal obstruction that needs surgery days after the theobromine has cleared. Count the wrappers you can find — it is the best dose estimate you will get, and it also tells the clinic what went down whole.

The seasonal spike is real: Christmas, Easter and Halloween drive the bulk of chocolate calls, and they share one hazard. An advent calendar, a stocking or an Easter basket is eaten unobserved, often overnight. That means the time is unknown, and time decides everything: the decontamination window may already be gone, in which case the plan shifts from emptying the stomach to bloodwork, ECG, IV fluids and monitoring through the 12–72 hour tail.

Cats and chocolate

Cats are more sensitive to methylxanthines per kilogram than dogs and far smaller, so a few grams matters. They also cannot taste sweetness — they carry a broken copy of the Tas1r2 gene, one half of the mammalian sweet-taste receptor — so exposure is almost always cocoa powder, baked goods, or licking a bowl rather than eating a bar. That is why chocolate cases are overwhelmingly canine, not because cats tolerate it better. A cat that has eaten chocolate should be assessed, not watched.

Puppies, pregnant dogs, and dogs with heart disease or epilepsy

• Puppies — small body mass against an adult-sized find, no discrimination about what they swallow, and less reserve if they vomit repeatedly or become hypoglycaemic.
• Pregnant and nursing dogs — methylxanthines cross the placenta and are excreted in milk, so the litter is exposed too.
• Dogs with heart disease — existing valve disease or an arrhythmia means the cardiotoxic band effectively starts lower; a heart rate a healthy dog tolerates may not be tolerated here.
• Dogs with epilepsy — methylxanthines lower the seizure threshold, so a dose in the tremor band can produce seizures in a dog already prone to them.
• Seniors and dogs with liver or kidney disease — slower clearance stretches an already long half-life, so signs last longer and monitoring runs longer.

If your dog is in any of these groups, say so in the first sentence when you call. It changes the threshold at which anyone recommends being seen.

Chocolate protein bars, hot cocoa, and 'just a lick of the bowl'

Cocoa powder is the most concentrated chocolate most kitchens contain — roughly 400–737 mg of theobromine per ounce, overlapping baker's chocolate at the low end and reaching well above it at the high end. One tablespoon (about 0.18 oz / 5 g) is 70–130 mg, which for a 20 lb (9 kg) dog is 8–14 mg/kg: GI territory at worst. Half a cup (about 1.4 oz / 40 g) is 560–1,040 mg, or 62–115 mg/kg for that same dog — the seizure band. Chocolate whey protein powder is milder per scoop but comes in tubs a dog can open. Caffeine-fortified protein bars stack a coating on top of 100–200 mg of added caffeine, which for a small dog is the larger half of the dose. A mug of made-up hot cocoa is mostly milk and low in theobromine, but the box of sachets on the counter is not. A genuine lick of frosting from a bowl is a fat-and-sugar question rather than a theobromine one — worth weighing the dog and running the numbers rather than guessing which it was.

Weigh the container, not the crumbs. The difference between a tablespoon of cocoa powder and half a cup is the difference between an upset stomach and a seizure, and both look identical on the floor.

Seven chocolate-toxicity facts most owners have never been told

None of this changes what you do in the next hour — the dose maths above does that. But these explain why chocolate behaves the way it does in a dog, and several of them are the reason a case that looked mild at midnight is still being treated at noon.

How to make this not happen again

Most repeat chocolate cases are the same house, the same dog, and a slightly different hiding place. Prevention that works is about barriers and habits, not about putting things higher up.

• Height is not containment. A medium dog on its hind legs reaches a standard kitchen counter, and a Labrador's nose finds a wrapped bar inside a zipped bag from across a room. "Up high" only works if there is also a door between the dog and the chocolate — a closed pantry, a latched cupboard, or the fridge.
• Guests' bags are the most common hidden source. Handbags, backpacks, gym bags and coat pockets routinely carry chocolate, protein bars, mints and gum — and the gum and mints may also contain xylitol, a separate and faster emergency. Give visitors somewhere to put their bag behind a closed door, and say why.
• Advent calendars, gift baskets and stockings are chocolate left at nose height for weeks. Hang calendars well above counter reach or keep them in a cupboard. Unwrap gift baskets the day they arrive — cellophane and ribbon are their own obstruction risk.
• Sort the Halloween or Easter haul on a table, never the floor. Kids, an open bag, candy spread over a rug is the classic setup. Store the bag in a closed cupboard afterwards, not on a bedroom shelf a dog can reach at 2am.
• Baking days are the highest-risk days in the house. Cocoa powder, chopped baker's chocolate and cooling brownies are the three most concentrated forms of theobromine there is, and they are out on the counter at once. Crate the dog or close the kitchen door until the surfaces are clear.
• Do not use cocoa bean shell mulch in a yard a dog uses. Pine bark, cedar or hardwood do the same job without smelling like a dessert. If a neighbour or landscaper has used it along a shared route, walk a different way.
• Teach "leave it" and "drop it" properly, and pay well for them. A restriction fails the one time a door is open; a trained response works in someone else's hallway. Practise with low-value items and trade up, so the dog learns that giving something up produces something better.
• Crate the dog or use a closed room during parties. Guests feed dogs, plates get set down, and front doors stand open. This is also the moment nobody is watching the coffee table.
• Weigh your dog and write the number and the date down. Every calculation on this page starts with body weight, and an estimate off by 30% moves a case between "monitor at home" and "go now". Most clinics will let you use their scale; a bathroom scale plus the hold-the-dog subtraction trick works for small dogs.
• Keep the wrapper. Photograph the package. Ounces, cacao percentage and whether it contained raisins, macadamias or xylitol are the difference between a precise dose and a worst-case assumption. The bin is the first place to look — before the drive, not after.

1. 1
   Weigh the dog this week

   Write the pounds (and kilograms) and the date on the card below. Re-weigh growing puppies monthly.
2. 2
   Find your nearest 24/7 emergency hospital before you need it

   Not the closest clinic — the closest one that is open at 3am. Note the drive time and whether they take walk-ins. Your own veterinarian's answering machine often names their after-hours referral hospital; write that name down.
3. 3
   Put a card on the fridge door

   Your own clinic's number and after-hours line; the 24/7 emergency hospital's number, address and drive time; ASPCA Animal Poison Control Center (888) 426-4435; Pet Poison Helpline (855) 764-7661; and your dog's current weight.
4. 4
   Save both poison lines in your phone right now

   At 1am, with a wrapper in one hand, nobody searches well. A contact card takes twenty seconds to make today.

Where to get help right now

If your dog has eaten chocolate and you are reading this section first: call your own veterinarian or your nearest 24-hour emergency hospital, and call one of the two poison lines below. They are staffed around the clock by veterinary toxicologists, they will run the dose calculation with you, and they will speak directly to the treating hospital.

The wrapper and a current weight are what turn an ingestion into a calculated mg/kg dose in under a minute. Without them the dose has to be assumed at the worst plausible amount, which means more monitoring and more cost for a dog whose real dose may have been low.

What treatment costs, and what each level buys

The figures below are typical US ranges as of 2026. Actual pricing varies widely by region, by whether it is a general practice during business hours or a 24-hour emergency hospital, and by how much treatment the dose requires. Ask for a written estimate before treatment begins; every clinic will provide one.

Sources for the numbers on this page