# Bismuth Subsalicylate: veterinary dose and monograph > Bismuth Subsalicylate is a veterinary gastrointestinal drug. An over-the-counter antidiarrhoeal / gastroprotectant used SHORT-TERM in DOGS for acute, uncomplicated diarrhoea and gastritis, and as part of Helicobacter triple therapy. Indications include acute, uncomplicated diarrhoea / gastroenteritis (short-term, dogs); gastritis / mild gastric irritation (mucosal protection); helicobacter-associated gastritis (component of triple therapy). This monograph lists 7 reference doses for dogs, cats, cattle, horses, pigs and ferrets, each with route, frequency and source, plus meat and milk withdrawal periods for food animals. Source: https://vetmasterji.com/drugs/bismuth-subsalicylate · Last reviewed: 2026-10-01 ## At a glance - **Drug class:** Gastrointestinal - **Also known as:** Pepto-Bismol, BSS, Pink bismuth - **Species with doses:** Dogs, Cats, Cattle, Horses, Pigs and Ferrets - **Routes:** PO - **Last reviewed:** 1 October 2026 ## Indications - Acute, uncomplicated diarrhoea / gastroenteritis (short-term, dogs) - Gastritis / mild gastric irritation (mucosal protection) - Helicobacter-associated gastritis (component of triple therapy) ## Bismuth Subsalicylate dose by species Doses are per administration unless stated. mg/kg doses scale with body weight; per-animal, per-quarter and infusion-rate doses are shown as the reference writes them. ### Dogs *Bismuth Subsalicylate doses for dogs* | Indication | Dose | Route | Frequency | Duration | | --- | --- | --- | --- | --- | | Acute diarrhoea / gastritis (short term) | 0.25–1 mL/kg of the 17.5 mg/mL suspension PO q6–8h (Papich: 1–3 mL/kg/day divided); ≤5 days | PO | q6–8h × ≤5 days | — | | Helicobacter gastritis (triple therapy) | 0.22 mL/kg of the 17.5 mg/mL suspension PO q4–6h, with metronidazole + amoxicillin, for 2–3 weeks | PO | q4–6h | 3 weeks | - Acute diarrhoea / gastritis (short term): Plumb’s p.153: 1 mL per 5 kg PO three times daily for no more than 5 days (Hall & Simpson); 0.25 mL/kg q4–6h up to 2 mL/kg q6–8h (Cote); uraemic gastritis 2 mL/kg q6–8h (Bartges). Papich 5e: 1–3 mL/kg/day in divided doses. Blackens stools; radio-opaque. - Helicobacter gastritis (triple therapy): Plumb’s p.153 (Hall 2000): metronidazole 15.4 mg/kg q8h + amoxicillin 11 mg/kg q8h + bismuth 0.22 mL/kg q4–6h for 3 weeks. Alternative (Leib 2007): 262 mg tablets q12h by weight (<5 kg ¼; 5–9.9 kg ½; 10–24.9 kg 1; >25 kg 2 tablets) with metronidazole 10 mg/kg and amoxicillin 15 mg/kg q12h for 2 weeks. ### Cats *Bismuth Subsalicylate doses for cats* | Indication | Dose | Route | Frequency | Duration | | --- | --- | --- | --- | --- | | Diarrhoea (short term, caution) | 0.5–1 mL/kg of the 17.5 mg/mL suspension PO q12h for up to 3 days (or 0.25 mL/kg q4–6h) | PO | q12h × ≤3 days | — | - Diarrhoea (short term, caution): Plumb’s p.153: 0.5–1 mL/kg q12h for 3 days (Scherk); 0.25 mL/kg q4–6h (Cote). Cats are salicylate-sensitive — avoid frequent or high doses and other salicylates/NSAIDs. Papich 5e (dogs and cats): 1–3 mL/kg/day divided. ### Cattle *Bismuth Subsalicylate doses for cattle* | Indication | Dose | Route | Frequency | Duration | Withdrawal | | --- | --- | --- | --- | --- | --- | | Calf diarrhoea | 30 mL per calf PO every 30 min for 8 doses, or 60 mL 2–4 times daily for 2 days | PO | per protocol | — | Withdrawal NOT established — treat as extra-label | - Calf diarrhoea: Papich 5e: 30 mL per calf q30min for 8 doses. Plumb’s p.153: 60 mL two to four times daily for 2 days (Corrective Mixture label); adults 2–3 oz PO 2–4 times daily (Braun). Follow the product label withdrawal. ### Horses *Bismuth Subsalicylate doses for horses* | Indication | Dose | Route | Frequency | Duration | | --- | --- | --- | --- | --- | | Diarrhoea (foals / adults) | 1–2 mL/kg of the 17.5 mg/mL suspension PO q6–8h | PO | q6–8h | — | - Diarrhoea (foals / adults): Papich 5e: 1–2 mL/kg q6–8h PO. Plumb’s p.153: foals 3–4 oz (90–120 mL) per 45 kg PO q6–8h (Madigan); 1 oz per 8 kg 3–4 times daily (Clark & Becht). ### Pigs *Bismuth Subsalicylate doses for pigs* | Indication | Dose | Route | Frequency | Duration | Withdrawal | | --- | --- | --- | --- | --- | --- | | Baby-pig diarrhoea | 2–5 mL per piglet PO 2–4 times daily for 2 days | PO | q6–12h × 2 days | — | Withdrawal NOT established — treat as extra-label | - Baby-pig diarrhoea: Plumb’s p.153 (Corrective Mixture label). Follow the product label withdrawal. ### Buffalo No buffalo-specific doses are on file, so buffalo are dosed as cattle. *Bismuth Subsalicylate doses for buffalo* | Indication | Dose | Route | Frequency | Duration | Withdrawal | | --- | --- | --- | --- | --- | --- | | Calf diarrhoea | 30 mL per calf PO every 30 min for 8 doses, or 60 mL 2–4 times daily for 2 days | PO | per protocol | — | Withdrawal NOT established — treat as extra-label | - Calf diarrhoea: Papich 5e: 30 mL per calf q30min for 8 doses. Plumb’s p.153: 60 mL two to four times daily for 2 days (Corrective Mixture label); adults 2–3 oz PO 2–4 times daily (Braun). Follow the product label withdrawal. ### Ferrets *Bismuth Subsalicylate doses for ferrets* | Indication | Dose | Route | Frequency | Duration | | --- | --- | --- | --- | --- | | Helicobacter mustelae (triple therapy) | 7.5–17.5 mg/kg | PO | q8h | 21–28 days | - Helicobacter mustelae (triple therapy): Plumb’s p.153: bismuth subsalicylate 17.5 mg/kg PO q8h with metronidazole 20 mg/kg and amoxicillin 20 mg/kg q12h for 21 days, plus famotidine and sucralfate (Johnson 2006); or 7.5 mg/kg with metronidazole 20 mg/kg and amoxicillin 30 mg/kg, all q8h for 3–4 weeks (Johnson-Delaney 2009). ## Contraindications Cats (salicylate sensitivity — avoid or use only with great caution). Concurrent NSAIDs/aspirin or bleeding disorders (additive salicylate/GI effects). Suspected GI perforation. Before abdominal radiographs (radio-opaque). Renal impairment. Known salicylate hypersensitivity. ## Species-specific warnings > **Caution:** Cats: Contains salicylate — cats metabolise salicylates poorly; avoid bismuth subsalicylate (toxicity risk). Use cat-appropriate antidiarrhoeals instead. ## Adverse effects - Black/grey discolouration of stool (mimics melaena) and sometimes the tongue - Constipation; salicylate effects with overuse - Radio-opacity (confounds radiographs) - Salicylate toxicity in cats / with overdose ## Drug interactions - NSAIDs/aspirin: additive salicylate effects (GI/bleeding) - Tetracyclines/fluoroquinolones: bismuth chelation reduces their absorption — separate dosing - Anticoagulants: salicylate may potentiate bleeding - Drugs requiring acid/absorption: altered by coating ## Pregnancy and lactation Avoid (salicylate); use other antidiarrhoeals if needed in pregnancy. ## Monitoring - Diarrhoea resolution (short-term use only — reassess if not improving in a few days) - Distinguish drug-induced black stool from true melaena - Avoid before planned abdominal radiographs - Salicylate effects with overuse / never in cats ## Toxicity and overdose Short-term canine use is well tolerated apart from black stools/constipation. Overuse or use in cats can cause SALICYLATE toxicity (vomiting, acid–base/electrolyte disturbance, hyperthermia, CNS signs). The black stool can mask or be mistaken for true GI bleeding (melaena) — a diagnostic pitfall. Management: For salicylate toxicity: discontinue, supportive care, IV fluids, correct acid–base/electrolytes, and standard salicylate-toxicosis management. Decontaminate large recent ingestions. Distinguish drug-related black stool from genuine melaena. ## Clinical pearls - A short-term OTC fix for acute canine diarrhoea/gastritis — coats the gut, binds toxins, and reduces secretion - AVOID in cats (salicylate) and don't stack with NSAIDs/aspirin - Warn owners stools turn BLACK (and it's radio-opaque) — don't mistake it for melaena or let it confound radiographs - Separate from tetracyclines/fluoroquinolones (bismuth chelation) and limit to a few days ## Mechanism of action In the gut, bismuth subsalicylate dissociates into bismuth (which coats/protects the mucosa, binds bacterial toxins, and has mild antibacterial action — including against Helicobacter) and salicylate (which inhibits prostaglandin synthesis, reducing intestinal secretion and inflammation — the antisecretory antidiarrhoeal effect). The bismuth reacts with luminal sulphur to form black bismuth sulphide, explaining the dark stool. ## Formulations and products - Oral suspension ~17.5 mg/mL (262 mg/15 mL) - 262 mg chewable tablet - Pepto-Bismol — 262 mg/15 mL suspension; 262 mg chewable, Suspension / chewable (human-label) ## Storage Suspension/tablets: 15–30 °C; shake suspension. Note it darkens stool and is radio-opaque. ## Before you use this dose > **Caution:** Reference doses for veterinary professionals. Confirm the dose against the product label, the patient’s condition, current guidance and local regulations before use; the attending veterinarian remains responsible for every clinical decision. ## Other gastrointestinal drugs - [Activated Charcoal](https://vetmasterji.com/drugs/activated-charcoal) - [Apomorphine](https://vetmasterji.com/drugs/apomorphine) - [Capromorelin](https://vetmasterji.com/drugs/capromorelin) - [Cimetidine](https://vetmasterji.com/drugs/cimetidine) - [Cisapride](https://vetmasterji.com/drugs/cisapride) - [Famotidine](https://vetmasterji.com/drugs/famotidine) - [Hyoscine Butylbromide (N-Butylscopolammonium)](https://vetmasterji.com/drugs/butylscopolamine) - [Lactulose](https://vetmasterji.com/drugs/lactulose) ## Frequently asked questions ### What is the dose of Bismuth Subsalicylate for dogs? Reference doses for Bismuth Subsalicylate in dogs: 0.25–1 mL/kg of the 17.5 mg/mL suspension PO q6–8h (Papich: 1–3 mL/kg/day divided); ≤5 days PO q6–8h × ≤5 days (Acute diarrhoea / gastritis (short term)); 0.22 mL/kg of the 17.5 mg/mL suspension PO q4–6h, with metronidazole + amoxicillin, for 2–3 weeks PO q4–6h for 3 weeks (Helicobacter gastritis (triple therapy)). Confirm against the label and the patient before use. ### What is the dose of Bismuth Subsalicylate for cats? Reference doses for Bismuth Subsalicylate in cats: 0.5–1 mL/kg of the 17.5 mg/mL suspension PO q12h for up to 3 days (or 0.25 mL/kg q4–6h) PO q12h × ≤3 days (Diarrhoea (short term, caution)). Confirm against the label and the patient before use. ### What is the dose of Bismuth Subsalicylate for cattle? Reference doses for Bismuth Subsalicylate in cattle: 30 mL per calf PO every 30 min for 8 doses, or 60 mL 2–4 times daily for 2 days PO per protocol (Calf diarrhoea). Confirm against the label and the patient before use. ### What is the withdrawal period for Bismuth Subsalicylate? Cattle, PO (Calf diarrhoea): Withdrawal NOT established — treat as extra-label; Pigs, PO (Baby-pig diarrhoea): Withdrawal NOT established — treat as extra-label. Follow the product label and national regulations where they differ. ### When should Bismuth Subsalicylate not be used? Cats (salicylate sensitivity — avoid or use only with great caution). Concurrent NSAIDs/aspirin or bleeding disorders (additive salicylate/GI effects). Suspected GI perforation. Before abdominal radiographs (radio-opaque). Renal impairment. Known salicylate hypersensitivity. ### What are the side effects of Bismuth Subsalicylate in animals? Black/grey discolouration of stool (mimics melaena) and sometimes the tongue; Constipation; salicylate effects with overuse; Radio-opacity (confounds radiographs); Salicylate toxicity in cats / with overdose. ## Sources - Plumb's Veterinary Drug Handbook - Merck Veterinary Manual, 11th edition - Papich, Papich Handbook of Veterinary Drugs, 5th edition --- VetMasterJi is a clinical decision-support and education platform for veterinary professionals and students. It does not provide veterinary advice, diagnosis or treatment for specific animals. All drug doses, calculators and differentials are references that must be independently verified before clinical use; the attending registered veterinarian remains solely responsible for every clinical decision.