Mucosal Protective Agent Pregnancy: Teratogenicity studies in mice, rats and rabbits at doses up to 50 times the human dose revealed no evidence of harm to the fetus. There are no adequate and well-controlled studies in pregnant women; this drug should be used during pregnancy only if clearly needed.

Sucralfate

Brand names: Antepsin

Sucralfate is a mucosal protectant used in the management of peptic ulcer disease and related mucosal damage. It acts locally rather than by reducing acid secretion.

Auto-extracted from the source labelling — not yet independently clinician-verified. These values were distilled from the UK SPC (or the US label where noted) but have not had a clinician sign-off. Confirm against the current SmPC before prescribing.

Adult dose

Dose: Active duodenal ulcer: 1 g four times per day on an empty stomach

Route: Oral

Frequency: Four times daily (maintenance therapy: twice a day)

Max: Not stated in source

Maintenance therapy: the recommended adult oral dosage is 1 g twice a day. While healing may occur during the first week or two, treatment should be continued for 4 to 8 weeks unless healing has been demonstrated by x-ray or endoscopic examination. Antacids may be prescribed as needed for relief of pain but should not be taken within one-half hour before or after sucralfate. Elderly: dose selection should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal or cardiac function and of concomitant disease or other drug therapy. Paediatric: safety and effectiveness in paediatric patients have not been established — verify any paediatric use against a children's formulary. SOURCE CAVEAT: no UK SPC was fetched; the above is US labelling (NuCare Pharmaceuticals sucralfate tablets, 2025-01-03) and must be verified against the UK SPC before publication.

Dose adjustments

Renal

No numeric adjustment stated. Sucralfate is known to be substantially excreted by the kidney and the risk of toxic reactions may be greater in patients with impaired renal function; because elderly patients are more likely to have decreased renal function, care should be taken in dose selection and it may be useful to monitor renal function. (US label cross-refers to a 'Chronic Renal Failure and Dialysis Patients' precautions section that was not included in the fetched extract.)

Dose auto-extracted from US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — not yet clinician-verified. Always confirm against the product SmPC and your local formulary before prescribing.

US labelling (FDA)

Reference — US labelling, may differ from UK

DOSAGE AND ADMINISTRATION Active Duodenal Ulcer. The recommended adult oral dosage for duodenal ulcer is 1 g four times per day on an empty stomach. Antacids may be prescribed as needed for relief of pain but should not be taken within one-half hour before or after sucralfate. While healing with sucralfate may occur during the first week or two, treatment should be continued for 4 to 8 weeks unless healing has been demonstrated by x-ray or endoscopic examination. Maintenance Therapy: The recommended adult oral dosage is 1 g twice a day. Elderly: In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater …

Source: US FDA prescribing information (openFDA / DailyMed), label dated 2025-01-03. Accessed 2026-06-12. US dosing and indications can differ from UK practice — use UK sources for prescribing decisions.

Contraindications

Known hypersensitivity reactions to the active substance or to any of the excipients

Side effects

Constipation (most frequent complaint, about 2%)
Diarrhoea, nausea, vomiting, gastric discomfort, indigestion, flatulence, dry mouth
Pruritus, rash
Dizziness, insomnia, sleepiness, vertigo
Back pain, headache
Post-marketing: hypersensitivity including dyspnoea, lip swelling, pruritus, rash and urticaria; bezoars (mainly in patients predisposed, e.g. delayed gastric emptying or enteral tube feeding)

Interactions

Reduced extent of absorption (bioavailability) when given simultaneously with: cimetidine, digoxin, fluoroquinolone antibiotics, ketoconazole, l-thyroxine, phenytoin, quinidine, ranitidine, tetracycline and theophylline
Warfarin — subtherapeutic prothrombin times reported in spontaneous and published case reports (two clinical studies showed no change in serum warfarin concentration or prothrombin time)
Interaction is non-systemic (binding in the GI tract): in all case studies to date, dosing the concomitant medication 2 hours before sucralfate eliminated the interaction; administer sucralfate separately from other drugs where altered bioavailability would be critical

Clinical monograph

How it works

In the acid environment of the stomach it forms a viscous, adherent complex that coats ulcerated mucosa, providing a physical barrier against acid, pepsin and bile.

Prescribing in practice

Sucralfate can bind many co-administered drugs and reduce their absorption (including certain antibiotics, levothyroxine, phenytoin and digoxin), so separate the timing of other medicines from sucralfate.
It contains aluminium, which can accumulate in significant renal impairment, so use with caution or avoid in this group and in patients on dialysis.
Constipation is common, and bezoar formation has been reported, particularly in critically ill patients, those with delayed gastric emptying or on enteral feeding.

Monitoring

No specific laboratory monitoring is required in most patients; be alert to aluminium accumulation in renal impairment and to gastrointestinal symptoms suggesting bezoar formation or obstruction.

Counselling the patient

Take it on an empty stomach, separately from food and from your other medicines, leaving a gap as advised.
Tell your pharmacist about all your other medicines, as the timing may need to be spaced out.
Report persistent constipation or abdominal pain.

Evidence & guidelines

Recognised option for mucosal protection in peptic ulcer disease (per the SPC).

Reference: BTS ICU stress ulcer prophylaxis guidelines; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways