Sucralfate Side Effects: What to Expect and When to Call Your Doctor

Sucralfate (brand name Carafate) is one of the better-tolerated GI medications available. Because it works locally in the gut and is minimally absorbed into the bloodstream (only about 3–5% of an oral dose reaches systemic circulation), most patients experience few systemic side effects. But that doesn't mean side effects don't occur — and a few serious ones require prompt medical attention. Here's what you need to know.

Common Side Effects of Sucralfate

The most frequently reported side effects affect the gastrointestinal system. Overall, adverse reactions requiring discontinuation of sucralfate are rare.

• Constipation (2–3%): The most common side effect. Sucralfate contains aluminum, which can slow bowel motility. If this is bothersome, increase water intake and dietary fiber. Talk to your doctor before taking a laxative, as some antacids interact with sucralfate.
• Dry mouth (xerostomia) (<0.5%): Some patients notice reduced saliva production. Staying well-hydrated and chewing sugar-free gum can help.
• Nausea (<1%): Mild nausea occasionally occurs. Taking sucralfate exactly as directed — on an empty stomach, 1 hour before meals — usually minimizes this.
• Flatulence (<1%): Increased gas may occur, particularly when starting the medication.
• Headache (<1%): Reported by a small percentage of patients. Usually mild and transient.
• Diarrhea (<1%): Less common than constipation. If diarrhea develops, inform your doctor.
• Skin rash or itching (<1%): Mild skin reactions are occasionally reported.
• Hyperglycemia (elevated blood sugar): Reported in diabetic patients using sucralfate. Monitor blood sugar more closely if you have diabetes.

Serious Side Effects: What to Watch For

While rare, several more serious effects can occur and require medical attention:

• Bezoar formation: A bezoar is a solid mass of undigested material that can form in the stomach or intestines. Sucralfate can contribute to bezoar formation, particularly in patients who have delayed gastric emptying, are on tube feedings, or take sucralfate for prolonged periods. Symptoms include bloating, persistent nausea, abdominal pain, and feeling full quickly. Report these symptoms to your doctor.
• Aluminum toxicity: Sucralfate contains aluminum, and while absorption is minimal in patients with normal kidney function, patients with chronic kidney disease or end-stage renal disease (especially those on dialysis) can accumulate aluminum. This can lead to aluminum intoxication with symptoms including bone pain, weakness, confusion, and neurological changes (encephalopathy). Sucralfate should be used cautiously — or avoided — in patients with significant renal impairment.
• Hypophosphatemia (low phosphate): Sucralfate can adsorb phosphate in the GI tract, reducing its absorption. Long-term use may cause low blood phosphate levels, particularly in patients on restricted diets or with malnutrition.
• Severe allergic reactions: Though rare, anaphylaxis-type reactions including hives (urticaria), angioedema (facial/tongue/throat swelling), difficulty breathing, and rhinitis have been reported post-marketing. If you experience these symptoms after taking sucralfate, seek emergency care immediately.

IMPORTANT: Never Inject the Oral Suspension

The sucralfate oral suspension must NEVER be administered intravenously. Fatal complications including pulmonary emboli and cerebral edema have occurred in medical settings where the suspension was accidentally given through an IV line. The suspension is strictly for oral use only.

Who Should Use Sucralfate with Caution?

Certain patients require special consideration:

• Kidney disease: Use with caution. Aluminum accumulation is a serious risk in patients with CKD or end-stage renal disease. Your doctor may monitor serum aluminum levels.
• Diabetes: Monitor blood glucose more closely. Hyperglycemia has been reported.
• Swallowing difficulties: Tablets should be used with caution in patients with impaired swallowing or altered gag reflex. The suspension may be preferable.
• Gastric motility disorders: Patients with delayed gastric emptying (gastroparesis) are at increased risk of bezoar formation.
• Elderly patients: More sensitive to side effects due to age-related changes in kidney and liver function. Start at the low end of the dosing range.

When to Call Your Doctor

Contact your doctor if you experience:

• Severe or worsening constipation not relieved by dietary changes
• Signs of a bezoar: persistent bloating, early satiety, vomiting, abdominal pain
• Skin rash, hives, swelling, or breathing difficulty (possible allergic reaction)
• New neurological symptoms (confusion, memory changes) — especially if you have kidney disease
• Symptoms that don't improve or worsen after 2–4 weeks of treatment

For more on sucralfate, read our guide on sucralfate drug interactions and our overview of what sucralfate is and how it works.