About 35 minutes ago, our 8kg (17.5 lb)

Go now. Call Animal Poisons Helpline 1300 869 738 (24/7, fee applies) and head to the nearest open emergency vet. 42.5 g of raisins in an 8 kg dog — even with no signs yet — is well past the watch-at-home line. The "just dried grapes, he'll get loose stool" reassurance is outdated folklore; grapes and raisins can cause acute kidney injury in dogs, the toxic dose is famously unpredictable, and "acting normal 35 minutes in" tells you nothing about what his kidneys will do in48 hours. He needs decontamination now, not tomorrow.

The helpline will tell you which Sydney hospital is actually open and staffed for emergencies right now — none of the clinics below came back flagged as 24 h.

Why your mother-in-law's advice is wrong this time

You remember correctly: grapes and raisins sit on every veterinary toxicology "go now" list. The leading modern hypothesis:

1. Tartaric acid (and potassium bitartrate) is the suspected nephrotoxin — and there is no safe minimum dose.

• Current consensus points to L-(+)-tartaric acid / potassium bitartrate (cream of tartar) as the nephrotoxic principle. Dogs appear to metabolise tartaric acid poorly; it (or its calcium salt) precipitates in the renal tubules and causes acute proximal tubular necrosis.
• Raisins are roughly 4× more concentrated than fresh grapes by weight (water has been removed), so per gram the toxic load is much higher than for table grapes.
• The clinically important fact: individual sensitivity is wildly variable. Some dogs develop AKI after a handful of raisins; others tolerate large amounts without issue. There is no established minimum safe dose in mg/kg. This is why even small exposures are taken seriously — there is no amount the vet will sign off as "definitely fine" in advance.
• Untreated course: nausea/vomiting and lethargy (often 6–24 h) → polyuric phase AKI (24–48 h, kidneys flood dilute urine but can't concentrate it) → oliguria/anuria (48–72 h, kidneys shut down) → uremic crisis. Once oliguria sets in, mortality rises sharply and damage can be irreversible.

2. The 2-hour decontamination window — and why home peroxide is the wrong call here.

• Vet-induced emesis (apomorphine IV/IM, or ropinirole eye drops) is highest-yield within roughly 2 hours of ingestion, while raisins are still in the stomach and before the nephrotoxin has cleared into the kidneys in quantity. After that window the value of emesis drops fast.
• Do not give hydrogen peroxide at home. Three reasons — and the second one is specific to your dog:

1. Re-aspiration of vomitus → aspiration pneumonia.
2. French Bulldogs are brachycephalic (stenotic nares, elongated soft palate, BOAS-prone airway), so any at-home vomiting attempt carries a meaningfully higher aspiration risk than in a mesocephalic breed.
3. Peroxide is a gastric irritant — prolonged retching/vomiting can cause haemorrhagic gastritis, which then masks whether he's vomiting from the raisins themselves.

• Bring the empty Sun-Maid box; the vet can confirm there's no chocolate/cocoa coating, and the lot/ingredient line is part of the case.

3. What the ER vet will likely do — the standard decontamination + renal support bundle.

• Decontamination: emesis (if still inside the window and no contraindication), then activated charcoal with a cathartic (sorbitol), often repeated once.
• Baseline bloods and urine before any treatment: BUN, creatinine, phosphorus, electrolytes, and urinalysis with urine specific gravity (USG). A USG that is inappropriately dilute in a dehydrated patient is an early red flag.
• IV crystalloid diuresis for ~48 h (e.g. Plasma-Lyte or 0.9 % NaCl at roughly 2× maintenance), titrated to urine output and renal values — the goal is to flush the nephrotoxin through the kidneys before it precipitates in the tubules.
• Antiemetic (maropitant) and GI protectant as needed.
• Serial monitoring at 0 h, 24 h, and 48 h: BUN, creatinine, phosphorus, USG. SDMA is sometimes added as an earlier marker of renal stress. Discharge only after renal values stay stable through the 48-hour mark — some dogs are kept an extra night if values are still trending.

Nearest vet clinics (this turn's map search — call before driving)

Source: OpenStreetMap via Geoapify; some hours from Google Maps. Hours change, and a listed clinic may not be open or may not see emergencies right now — phone first. None of these came back flagged as 24-hour emergency on the listing.

• Pyrmont Vet (Pyrmont Veterinary Hospital) — 1 Scott St, Pyrmont NSW 2009 · ~1.5 km · (02) 8203 0355
• Potts Point Veterinary Hospital — 41b Elizabeth Bay Rd, Elizabeth Bay NSW 2011 · ~1.8 km · +61 2 8097 0060
• Glebe Veterinary Hospital — 113 Glebe Point Rd, Glebe NSW 2037 · ~2.2 km · +61 2 9660 1771
• Surry Hills Vet (Southern Cross Veterinary Clinic) — Cleveland St, Redfern NSW 2010 · ~2.5 km · (02) 9699 3951

For a true after-hours emergency hospital in Sydney, the Animal Poisons Helpline will direct you to the open one (commonly Sydney Animal Hospitals Norrie, SASH, or Animal Referral Hospital Homebush). Triple Zero 000 is not a pet line.

Animal poison line — this turn's lookup (Australia)

• Animal Poisons Helpline: 1300 869 738 · 24/7 · consultations with a Poisons Information Consultant from AUD 75 · animalpoisons.com.au

What we can't do here: compute a "safe amount," tell you he's fine because he looks fine, or replace the exam. The vet — or the helpline vet — makes the dose, treatment, and discharge call.