Drug Monograph

Sucralfate

Brand name: Carafate

GI Mucosal Protectant · Oral
Pharmacokinetic Profile
Duration of Action
Up to 6 h
Systemic Absorption
<5%
Protein Binding
N/A (local action)
Bioavailability
<5% (oral)
Metabolism
GI tract (local)
Clinical Information
Drug Class
GI Mucosal Protectant
Available Doses
1 g tablet; 1 g/10 mL suspension
Route
Oral
Renal Adjustment
Use with caution (Al accumulation)
Hepatic Adjustment
No adjustment required
Pregnancy
Compatible (minimal absorption)
Lactation
Compatible (minimal absorption)
Schedule
Rx Only
Generic Available
Yes
Rx

Indications

IndicationApproved PopulationTherapy TypeStatus
Active duodenal ulcer — short-term treatmentAdultsMonotherapyFDA Approved
Duodenal ulcer — maintenance therapyAdultsMonotherapyFDA Approved

Sucralfate is a locally acting mucosal protectant approved specifically for duodenal ulceration. Its efficacy in duodenal ulcer healing has been shown to be comparable to histamine H2-receptor antagonists in controlled trials. Treatment duration for active ulcers is typically 4 to 8 weeks, with maintenance dosing available for recurrence prevention. The drug does not alter the underlying disease course or prevent future recurrences.

Off-Label Uses

Stress ulcer prophylaxis in ventilated ICU patients — Evidence quality: Moderate. Some data suggest reduced nosocomial pneumonia risk compared to acid-suppressive agents, though PPIs have largely supplanted sucralfate in contemporary practice.

GERD in pregnancy — Evidence quality: Low. ACG guidelines list sucralfate as an option during pregnancy given its negligible systemic absorption.

Hemorrhagic radiation proctitis (sucralfate enema) — Evidence quality: Moderate. ASCRS guidelines acknowledge sucralfate retention enemas as an effective option for chronic radiation proctitis with rectal bleeding.

Oral mucositis from chemotherapy/radiation — Evidence quality: Low. Limited evidence for benefit; some oncology protocols include sucralfate swish-and-spit for oropharyngeal mucositis.

NSAID-related dyspepsia and gastric erosions — Evidence quality: Low. Data suggest symptom improvement similar to H2 blockers, but PPIs are generally preferred.

Topical wound healing (venous ulcers, burns) — Evidence quality: Low. Case series suggest benefit through growth factor potentiation, but large controlled trials are lacking.

Dose

Dosing

Adult Dosing by Clinical Scenario

Clinical ScenarioStarting DoseMaintenance DoseMaximum DoseNotes
Active duodenal ulcer — healing phase1 g QID1 g QID for 4–8 weeks4 g/dayAdminister on empty stomach, 1 h before meals and at bedtime
Continue for 4–8 wk unless healing confirmed by endoscopy
Duodenal ulcer — maintenance / recurrence prevention1 g BID1 g BID2 g/dayInitiated after successful healing phase
Optimal maintenance duration not established beyond 1 year
Stress ulcer prophylaxis — mechanically ventilated patients (off-label)1 g QID1 g QID4 g/dayVia nasogastric tube; administer as suspension
PPIs/H2RAs now more commonly used in most ICU protocols
GERD symptom relief in pregnancy (off-label)1 g QID1 g QID4 g/dayOn empty stomach; may be used when antacids insufficient
ACG guideline-supported option in pregnancy
Radiation proctitis — rectal administration (off-label)2 g paste enema2 g enema BID4 g/day (rectal)2 tablets crushed in 4.5 mL water as paste; retain for 30 min
Per ASCRS clinical practice guidelines

Special Population Adjustments

PopulationStarting DoseMaintenance DoseMaximum DoseNotes
Elderly1 g QID1 g BID–QID4 g/dayStart cautiously; monitor renal function and concomitant medications
Aluminum accumulation risk increases with declining renal function
Renal impairment / DialysisUse with extreme caution or avoidAluminum does not cross dialysis membranes; accumulation and toxicity reported
Monitor serum aluminum if used; consider alternative agents
PediatricSafety and efficacy not establishedNot FDA-approved for pediatric use
Off-label topical use studied in post-adenotonsillectomy analgesia
Clinical Pearl: Timing Is Everything

Sucralfate must be taken on an empty stomach — at least 1 hour before meals — because food and gastric acid activate the drug’s polymerization. Concomitant medications should be given at least 2 hours before sucralfate to avoid binding-related absorption reduction. Antacids, if needed for pain, should be separated by at least 30 minutes.

PK

Pharmacology

Mechanism of Action

Sucralfate is a basic aluminum salt of sucrose octasulfate that works through a local, non-systemic mechanism. In the acidic gastric environment (pH <4), sucralfate undergoes cross-linking and polymerization to form a viscous, paste-like substance. This gel adheres selectively to ulcerated mucosa by binding to positively charged proteins in the ulcer exudate, creating a physical barrier that shields the lesion from acid, pepsin, and bile salts. The drug also inhibits pepsin activity by approximately 32% at therapeutic doses and adsorbs bile salts that would otherwise damage healing tissue. Beyond its barrier properties, sucralfate stimulates local prostaglandin synthesis, which enhances bicarbonate secretion and mucus production. It also binds epidermal growth factor and fibroblast growth factor, concentrating these mediators at the ulcer site and promoting tissue regeneration. Each gram of sucralfate provides approximately 14–16 mEq of acid-neutralizing capacity, though this is not considered its primary therapeutic mechanism.

ADME Profile

ParameterValueClinical Implication
Absorption<5% systemically absorbed; onset of action 1–2 hPredominantly local effect; systemic adverse reactions uncommon
DistributionDistributes to GI mucosal lesions; no significant systemic distributionDrug remains concentrated at the ulcer site; no CNS or peripheral tissue effects expected
MetabolismDegraded locally in GI tract to aluminum + sucrose octasulfate; not hepatically metabolizedNo CYP-mediated metabolic interactions; no hepatic dose adjustment needed
EliminationSmall absorbed fraction excreted renally; bulk excreted in fecesAluminum clearance depends on renal function — accumulation risk in CKD/dialysis patients
SE

Side Effects

Sucralfate has a favorable safety profile owing to its negligible systemic absorption. In clinical trials involving over 2,700 patients, adverse effects were reported in 4.7% overall. The most clinically significant concern is constipation.

≥10% Very Common
Adverse EffectIncidenceClinical Note
No adverse effects reported at ≥10% incidence in clinical trials (FDA PI)
1–10% Common
Adverse EffectIncidenceClinical Note
Constipation2%Most frequently reported adverse effect; related to aluminum content; manage with adequate fluid intake and fiber
Uncommon Adverse Effects (<0.5%)

The following were reported in fewer than 0.5% of patients in clinical trials: diarrhea, dry mouth, flatulence, gastric discomfort, indigestion, nausea, vomiting, pruritus, rash, dizziness, insomnia, sleepiness, vertigo, back pain, and headache.

Serious Serious (Regardless of Frequency)
Adverse EffectEstimated FrequencyTypical OnsetRequired Action
Aluminum toxicity (osteodystrophy, encephalopathy)RareWeeks to months with chronic use in renal impairmentDiscontinue sucralfate; check serum aluminum; consider deferoxamine chelation
Gastric bezoar formationRareWeeks to months; higher risk with enteral feeds or gastroparesisDiscontinue; may require endoscopic removal; avoid in patients with delayed gastric emptying
Anaphylaxis / hypersensitivity (edema of mouth, lips, pharynx, urticaria, dyspnea)Very rareMinutes to hours after first or subsequent dosesEmergency treatment; permanent discontinuation; document allergy
HypophosphatemiaRareWeeks of chronic useMonitor phosphate levels; supplement if needed; consider discontinuation
Hyperglycemia (in diabetic patients using suspension)RareDays after initiationIncrease blood glucose monitoring; adjust antidiabetic therapy as needed
Fatal pulmonary/cerebral emboli (with inadvertent IV administration)Very rareImmediateNEVER administer intravenously — oral/enteral route only
Discontinuation Discontinuation Rates
Adults — Overall
Rarely led to discontinuation
In trials of over 2,700 patients, adverse effects were reported in only 4.7% and drug discontinuation due to adverse events was uncommon (FDA PI). Specific discontinuation rates were not separately quantified in the pivotal trials.
Tolerability Profile
Favorable
Top reasons for stopping: Constipation (most common), gastrointestinal discomfort. The overall adverse event rate of 4.7% and the local mechanism of action make sucralfate one of the better-tolerated GI agents.
Managing Constipation

Constipation is the most clinically relevant adverse effect of sucralfate, attributable to its aluminum content. Encourage patients to maintain adequate hydration (1.5–2 L/day) and dietary fiber intake. An osmotic laxative such as polyethylene glycol may be added if constipation persists. Patients with pre-existing constipation or gastroparesis should be monitored closely, as they are also at increased risk of bezoar formation.

Int

Drug Interactions

Sucralfate interacts with other drugs primarily through a non-systemic binding mechanism in the GI tract, not through hepatic CYP enzyme pathways. It physically adsorbs co-administered medications, reducing their bioavailability. In virtually all studied cases, separating the interacting drug by at least 2 hours before sucralfate eliminates the interaction.

Major Fluoroquinolones (ciprofloxacin, norfloxacin, ofloxacin)
MechanismChelation of quinolone by aluminum ions in the GI lumen
EffectMarkedly reduced fluoroquinolone absorption, potentially leading to therapeutic failure
ManagementAdminister fluoroquinolone at least 2 h before sucralfate; do not give simultaneously
FDA PI
Major Levothyroxine
MechanismGI-tract binding of levothyroxine by sucralfate
EffectReduced thyroid hormone absorption; may cause hypothyroid symptoms or elevated TSH
ManagementSeparate by at least 4 hours; monitor TSH if co-prescribed
FDA PI
Major Phenytoin
MechanismAdsorption of phenytoin in the GI tract by sucralfate
EffectDecreased phenytoin bioavailability and serum concentrations, risking seizure breakthrough
ManagementGive phenytoin at least 2 h before sucralfate; monitor phenytoin levels
FDA PI
Moderate Warfarin
MechanismPotential GI-tract binding; evidence is conflicting
EffectCase reports of subtherapeutic INR, though two clinical studies showed no interaction
ManagementSeparate administration by 2 h; monitor INR closely when starting or stopping sucralfate
FDA PI / Case Reports
Moderate Digoxin
MechanismGI-tract adsorption reducing digoxin absorption
EffectReduced digoxin serum concentration; risk of subtherapeutic levels
ManagementAdminister digoxin at least 2 h before sucralfate; monitor digoxin levels
FDA PI
Moderate Ketoconazole
MechanismKetoconazole requires acid for absorption; sucralfate’s mild alkalizing effect and binding reduce absorption
EffectReduced ketoconazole bioavailability; potential antifungal treatment failure
ManagementGive ketoconazole at least 2 h before sucralfate
FDA PI
Moderate Tetracycline
MechanismChelation by aluminum and GI-tract binding
EffectDecreased tetracycline absorption
ManagementSeparate by at least 2 h; administer tetracycline first
FDA PI
Minor Antacids (aluminum/magnesium hydroxide)
MechanismAntacids raise gastric pH, reducing sucralfate polymerization and ulcer adherence
EffectPotentially reduced efficacy of sucralfate
ManagementDo not give antacids within 30 minutes before or after sucralfate
FDA PI
Clinical Pearl: The 2-Hour Rule

The overwhelming majority of sucralfate drug interactions can be managed with a simple timing strategy: give the interacting medication at least 2 hours before sucralfate. This separation window has been validated in pharmacokinetic studies for cimetidine, ciprofloxacin, digoxin, norfloxacin, ofloxacin, and ranitidine. When a patient takes multiple medications, careful scheduling of sucralfate at the end of the dosing window is the most practical approach.

Mon

Monitoring

  • Renal Function Baseline; periodically in at-risk patients
    Routine
    Serum creatinine and estimated GFR before initiation. Particularly important in elderly patients and those with known CKD, as aluminum accumulation risk increases with declining renal clearance.
  • Serum Aluminum If CKD or dialysis patient
    Trigger-based
    Monitor serum aluminum levels in patients with renal impairment, especially dialysis patients. Elevated levels warrant discontinuation and possible chelation with deferoxamine.
  • Blood Glucose Ongoing in diabetic patients
    Trigger-based
    The oral suspension contains glucose and may cause hyperglycemia in diabetic patients. Monitor blood glucose more frequently when initiating sucralfate suspension and adjust antidiabetic therapy as needed.
  • Serum Phosphate Periodically with chronic use
    Trigger-based
    Aluminum-containing compounds can bind dietary phosphate. Check serum phosphate if patient develops weakness, bone pain, or is on prolonged therapy, particularly in malnourished or CKD populations.
  • Ulcer Healing Endoscopy at 4–8 weeks
    Routine
    Healing should be confirmed by endoscopy or radiography. If ulcer persists after 8 weeks of therapy, reassess diagnosis and consider alternative treatments including testing for H. pylori.
  • Drug Levels (interacting medications) As clinically indicated
    Trigger-based
    Monitor levels or clinical effect of narrow-therapeutic-index drugs given concurrently (phenytoin, digoxin, warfarin/INR, levothyroxine/TSH) when starting, adjusting, or stopping sucralfate.
CI

Contraindications & Cautions

Absolute Contraindications

  • Known hypersensitivity to sucralfate or any excipient — anaphylactic reactions have been reported post-marketing
  • Intravenous administration — fatal pulmonary and cerebral emboli have occurred with inadvertent IV use; sucralfate must only be given orally or enterally

Relative Contraindications (Specialist Input Recommended)

  • End-stage renal disease / dialysis — aluminum accumulation and toxicity (osteodystrophy, encephalopathy) are well-documented; aluminum does not cross dialysis membranes. Consider alternative mucosal protective agents.
  • Patients on multiple narrow-therapeutic-index drugs — the extensive binding interactions may be difficult to manage with timing alone in complex medication regimens. Coordination with pharmacy is recommended.

Use with Caution

  • Chronic kidney disease (non-dialysis) — monitor serum aluminum and renal function periodically
  • Diabetes mellitus — the oral suspension contains glucose; hyperglycemia has been reported. Close glycemic monitoring recommended.
  • Dysphagia or impaired gag/cough reflex — risk of aspiration with oral suspension
  • Delayed gastric emptying / gastroparesis — increased risk of bezoar formation
  • Enteral tube feeding — bezoar formation risk is higher with concurrent tube feeds; the tube may also become occluded
  • Elderly patients — more likely to have reduced renal function and polypharmacy; start at conservative end of dosing range
FDA Safety Warning Fatal Complications with Intravenous Administration

Fatal complications including pulmonary and cerebral emboli have been reported with inappropriate intravenous administration of sucralfate oral suspension. Sucralfate must be administered only by the oral route. Healthcare facilities should ensure that sucralfate is clearly labeled for oral/enteral use only and stored separately from injectable medications to prevent inadvertent IV administration.

Pt

Patient Counselling

Purpose of Therapy

Sucralfate works by forming a protective coating over your ulcer, shielding it from stomach acid so it can heal. It does not reduce the amount of acid your stomach produces — it provides a physical barrier. Treatment typically lasts 4 to 8 weeks for active ulcers, and your doctor may then switch you to a lower maintenance dose to help prevent recurrence.

How to Take

Take sucralfate on an empty stomach, ideally 1 hour before meals and at bedtime. If you are using the liquid suspension, shake the bottle well before each dose. Do not freeze the suspension. Take sucralfate at the same times each day. If you are taking other medications, take them at least 2 hours before your sucralfate dose to ensure they are absorbed properly.

Constipation
Tell patient Constipation is the most common side effect, occurring in about 1 in 50 people. It is usually mild. Drinking plenty of water and eating fiber-rich foods can help prevent it. An over-the-counter stool softener is safe to use if needed.
Call prescriber If constipation becomes severe, if you have no bowel movement for 3 or more days, or if you develop abdominal pain, bloating, or vomiting.
Medication Timing
Tell patient Sucralfate can interfere with the absorption of many other medicines if taken at the same time. Always take your other medications at least 2 hours before sucralfate. If you take antacids for pain relief, do not take them within 30 minutes of sucralfate.
Call prescriber If you are prescribed a new medication while taking sucralfate, confirm with your pharmacist or doctor that the timing is appropriate. Report any signs that your other medications may not be working as well (e.g., breakthrough seizures if on phenytoin, thyroid symptoms if on levothyroxine).
Treatment Duration and Expectations
Tell patient You may feel symptom relief within the first 1–2 weeks, but continue taking sucralfate for the full course prescribed (usually 4–8 weeks) even if you feel better. Stopping early may allow the ulcer to persist. Sucralfate heals the current ulcer but does not prevent future ulcers.
Call prescriber If symptoms worsen or do not improve after 2 weeks. If you notice blood in your stool, vomiting blood, or severe abdominal pain — seek urgent medical attention.
Allergic Reactions
Tell patient Although very rare, allergic reactions can occur. Be aware of signs such as swelling of the face, lips, or throat, difficulty breathing, hives, or widespread rash.
Call prescriber Seek emergency medical attention immediately if you develop any of these symptoms after taking sucralfate.
Diabetes and the Liquid Formulation
Tell patient The oral suspension contains sugar, which may affect blood glucose levels. If you have diabetes, monitor your blood sugar more carefully after starting sucralfate suspension. The tablet formulation may be preferred if glucose control is a concern.
Call prescriber If your blood glucose readings are consistently higher than usual after starting sucralfate suspension, contact your doctor for possible dose adjustment of your diabetes medication.
Ref

Sources

Regulatory (PI / SmPC)
  1. Carafate (sucralfate) Oral Suspension — FDA-Approved Prescribing Information, revised December 2022. Allergan USA, Inc. FDA Label (Suspension) Current FDA-approved label for sucralfate oral suspension; source for approved indications, dosing, adverse reactions, and contraindications.
  2. Carafate (sucralfate) Tablets — FDA-Approved Prescribing Information, revised 2013. Aptalis Pharma US, Inc. FDA Label (Tablets) FDA-approved label for sucralfate tablets; includes maintenance dosing (1 g BID) and clinical trial healing rate data.
Key Clinical Trials
  1. Garnett WR. Sucralfate — alternative therapy for peptic-ulcer disease. Clin Pharm. 1982;1(4):307–314. PubMed: 6764389 Early clinical review establishing sucralfate efficacy as comparable to cimetidine and intensive antacid therapy for duodenal ulcer healing.
  2. Driks MR, Craven DE, Celli BR, et al. Nosocomial pneumonia in intubated patients given sucralfate as compared with antacids or histamine type 2 blockers. N Engl J Med. 1987;317(22):1376–1382. PubMed: 2891032 Landmark trial showing reduced nosocomial pneumonia with sucralfate for stress ulcer prophylaxis compared to pH-raising agents.
  3. Kochhar R, Patel F, Dhar A, et al. Radiation-induced proctosigmoiditis: prospective, randomized, double-blind controlled trial. Dig Dis Sci. 1991;36(1):103–107. PubMed: 1670631 RCT demonstrating superiority of rectal sucralfate over oral sulfasalazine for short-term treatment of radiation proctitis.
Guidelines
  1. Katz PO, Dunbar KB, Schnoll-Sussman FH, et al. ACG Clinical Guideline for the Diagnosis and Management of Gastroesophageal Reflux Disease. Am J Gastroenterol. 2022;117(1):27–56. DOI: 10.14309/ajg.0000000000001538 ACG guideline listing sucralfate as a treatment option for GERD during pregnancy.
  2. Paquette IM, Vogel JD, Abbas MA, et al. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Treatment of Chronic Radiation Proctitis. Dis Colon Rectum. 2018;61(10):1135–1140. PubMed: 30192320 ASCRS guideline supporting sucralfate retention enemas as effective treatment for rectal bleeding from chronic radiation proctitis.
  3. Ye Z, Reintam Blaser A, Lytvyn L, et al. Gastrointestinal bleeding prophylaxis for critically ill patients: a clinical practice guideline. BMJ. 2020;368:l6722. PubMed: 31907223 BMJ clinical practice guideline on GI bleeding prophylaxis in ICU; contextualizes sucralfate’s role relative to PPIs and H2RAs.
Mechanistic / Basic Science
  1. McCarthy DM. Sucralfate. N Engl J Med. 1991;325(14):1017–1025. PubMed: 1886624 Comprehensive NEJM review of sucralfate’s mechanism of action, covering cytoprotective effects, growth factor binding, and prostaglandin stimulation.
  2. Masuelli L, Tumino G, Turriziani M, et al. Topical use of sucralfate in epithelial wound healing: clinical evidences and molecular mechanisms of action. Recent Pat Inflamm Allergy Drug Discov. 2010;4(1):25–36. PubMed: 19832693 Review of sucralfate’s wound-healing properties including FGF and EGF binding that underpin its off-label topical applications.
Pharmacokinetics / Special Populations
  1. Sulochana SP, Syed M, Chandrasekar DV, et al. Clinical Drug-Drug Pharmacokinetic Interaction Potential of Sucralfate with Other Drugs: Review and Perspectives. Eur J Drug Metab Pharmacokinet. 2016;41(5):469–503. PubMed: 27086359 Comprehensive review of sucralfate’s drug interaction profile with pharmacokinetic data for each documented interaction.
  2. Hemstreet BA. Use of sucralfate in renal failure. Ann Pharmacother. 2001;35(3):360–364. PubMed: 11261535 Evaluates aluminum accumulation risk from sucralfate in patients with renal impairment; supports caution or avoidance in dialysis patients.
  3. Steiner K, Bühring KU, Faro HP, et al. Sucralfate: pharmacokinetics, metabolism and selective binding to experimental gastric and duodenal ulcers in animals. Arzneimittelforschung. 1982;32(5):512–518. PubMed: 6896647 Foundational pharmacokinetic study demonstrating minimal systemic absorption and selective ulcer-site binding of sucralfate.