Bismuth subsalicylate

How it works

It exerts a local antisecretory, anti-inflammatory and antibacterial action on the gastrointestinal mucosa, with the salicylate moiety contributing antisecretory effects within the gut.

Prescribing in practice

• Because it releases salicylate, it should be avoided in children and adolescents with viral illness owing to the risk of Reye's syndrome, and used with caution in patients with salicylate hypersensitivity or those taking other salicylates or anticoagulants.
• It can cause harmless but striking blackening of the tongue and stools, which should not be mistaken for melaena.
• Avoid prolonged high-dose use because of the potential for bismuth accumulation and salicylate toxicity.

Monitoring

No routine monitoring is required for short-term use; review if symptoms persist or with prolonged or high-dose administration.

Counselling the patient

• Your stools and tongue may turn black, which is harmless and reversible.
• Do not give salicylate-containing products to children or teenagers with a feverish illness.
• Tell your prescriber if you take blood-thinning medicines or other aspirin-like drugs.

Evidence & guidelines

Bismuth subsalicylate has long-established use for gastrointestinal symptom relief and within combination Helicobacter pylori eradication regimens.