Drug reference

Bismuth subsalicylate

Antacid · Anti-ulcer agent

Also known as Kaopectate, Kao-Tin

AntacidAnti-ulcer agentATC A07BB

CDSCO approvedSchedule HATC A07BB

EXCRETION

—

not curated

INTERACTIONS

8 major

SEVERE in our sources

PREGNANCY

Manufacturer advises avoid unless essential—no information available.

FDA category + note

Top interactionssee all 8 →

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Mechanism

Bismuth subsalicylate is thought to act by decreasing prostaglandin synthesis in the intestinal mucosa, thereby reducing chloride secretion. It also has weak antibacterial action, which may contribute to its prophylactic value in travellers' diarrhoea and its role in Helicobacter pylori eradication.

Indications

Helicobacter pylori eradication (in combination with other drugs)Travellers' diarrhoea (prophylactic value)In combination with antibiotics for Helicobacter pylori eradicationPrevention of ulcer recurrencePrevention and treatment of traveler's diarrheaOther forms of episodic diarrheaAcute gastroenteritisIndigestionNauseaAbdominal crampsTraveler’s diarrheaProphylaxis of traveler’s diarrhea

Dosing

Adult: For Helicobacter pylori eradication: 525 mg 4 times a day for 7 days for first- and second-line eradication therapy; 10 days for third-line eradication therapy. For travellers' diarrhoea: 60 ml oral suspension 6 hourly.

Pharmacokinetics

Excretion

99% of bismuth passes unabsorbed into feces; salicylate absorbed in stomach and small intestine

Contraindications

Children under 16 years (risk of Reye’s syndrome)
Children and young adults <20 years of age with viral illness-associated fever (risk of Reye’s syndrome)
History of hypersensitivity to aspirin or other salicylates
Blood clotting disorders
Gout
Children (warning regarding Reye's syndrome due to salicylate content)

Side effects

Common

Black faecesBlack tongueBlackening of stools (due to formation of bismuth sulfide in the colon)Dark stools (mistaken for melena)Black staining of the tonguetemporary darkening of the tongueconstipationtinnitus

Serious

Reye’s syndrome (in children and young adults with viral illness)
Salicylate poisoning (hyperventilation, tinnitus, deafness, vasodilatation, sweating)
Bismuth overdose (acute encephalopathy with confusion, myoclonus, tremor, dysarthria, gait disturbances, gastrointestinal disturbances, skin reactions, discolouration of mucous membranes, renal impairment)
Reye's syndrome (in children due to salicylate)
CNS side effects
Hearing loss
Tinnitus