Does Mesalamine Cause Heartburn? An In-Depth Look at Side Effects and Management

October 9, 2025 •

4 min read

According to reputable sources like the Crohn's & Colitis Foundation and MedlinePlus, heartburn is listed among the common side effects reported by patients taking mesalamine. While this anti-inflammatory medication is crucial for managing conditions such as ulcerative colitis, it can sometimes lead to gastrointestinal discomfort that includes a burning sensation in the chest or throat.

Quick Summary

Mesalamine can cause heartburn and other gastrointestinal issues. Factors like the medication's formulation and how it's taken can influence side effects. Management involves timing doses correctly, adjusting diet, and consulting a healthcare provider to differentiate between side effects and disease flare-ups.

Key Points

Heartburn is a documented side effect: Numerous health resources, including the Crohn's & Colitis Foundation, list heartburn as a possible side effect of mesalamine.
Oral formulations can cause irritation: Even though mesalamine's action targets the colon, oral tablets and capsules pass through the upper digestive tract, which can lead to gastric irritation and acid reflux.
Formulation and timing matter: The specific oral brand (e.g., Lialda vs. Asacol HD) and whether you take it with food or on an empty stomach can significantly impact GI side effects like heartburn.
Lifestyle changes can help: Strategies such as eating smaller meals, avoiding fatty and spicy foods, staying upright after a dose, and maintaining hydration can mitigate heartburn.
Monitor for acute intolerance syndrome: Watch for severe abdominal pain, bloody diarrhea, or fever, which could indicate a medication intolerance rather than a flare-up of ulcerative colitis.
Consult your healthcare provider: It is crucial to inform your doctor about persistent or severe heartburn, as they can recommend adjustments, rule out complications, and ensure your medication is working effectively.

Mesalamine, also known as 5-aminosalicylic acid (5-ASA), is a common and effective medication prescribed to treat inflammatory bowel disease (IBD), particularly ulcerative colitis. It works by reducing inflammation in the lining of the large intestine. While its action is intended to be local to the colon, a significant percentage of patients experience systemic or upper gastrointestinal side effects, including heartburn.

The Link Between Mesalamine and Heartburn

Heartburn is the uncomfortable burning sensation behind the breastbone caused by stomach acid flowing back into the esophagus. Although mesalamine's therapeutic effect is primarily in the lower digestive tract, oral formulations must first pass through the stomach and small intestine. This transit can be a source of irritation, contributing to upper gastrointestinal symptoms like heartburn, indigestion, and belching.

Several factors can influence the likelihood and severity of this side effect:

Dosage Form: The protective coatings on different mesalamine formulations (delayed-release vs. extended-release) are designed to release the active ingredient at specific points in the digestive tract. If a coating is not working as intended or the timing of administration is incorrect, it could lead to improper absorption and gastric irritation.
Individual Sensitivity: Some patients may simply be more sensitive to the active compound or inactive ingredients in the medication.
Interactions: Interactions with other medications, such as some antacids, can interfere with how mesalamine is absorbed, potentially causing stomach upset.
Underlying Condition: It is also possible for the symptoms to be related to the underlying inflammatory condition itself, or an acute intolerance syndrome, which makes it challenging to distinguish between the disease and a medication side effect.

Common Gastrointestinal Side Effects

Heartburn is just one of several gastrointestinal side effects associated with mesalamine use. Patients commonly report a range of related issues:

Nausea and vomiting
Stomach or abdominal pain
Gas (flatulence) and burping
Diarrhea or constipation
Indigestion (dyspepsia)
Loss of appetite

Managing Mesalamine-Induced Heartburn

If you experience heartburn while taking mesalamine, several strategies can help minimize discomfort. Always consult your healthcare provider before making any changes to your medication or diet.

Proper Administration

Follow Directions Carefully: Different oral mesalamine brands have specific instructions for taking them with or without food. Taking a medication like Lialda, which should be taken with food, on an empty stomach could increase the risk of side effects like indigestion. Conversely, taking Asacol HD with food is not recommended.
Stay Upright: After taking your dose, avoid lying down immediately. Remaining upright can help prevent acid reflux.
Avoid Crushing or Chewing: Never crush, break, or chew delayed-release or extended-release tablets or capsules unless specifically instructed by your doctor or pharmacist. The special coating is essential for ensuring the medication is released in the correct part of the digestive tract.
Check Antacid Use: Some antacids can interfere with the function of certain mesalamine formulations, like Apriso. Always discuss the use of antacids with your doctor or pharmacist.

Dietary and Lifestyle Adjustments

Eat Smaller, More Frequent Meals: Large meals can put pressure on the stomach and trigger reflux. Eating smaller meals more often may help.
Stay Hydrated: Drinking plenty of fluids, especially water, throughout the day can aid digestion and is particularly important with mesalamine to help prevent kidney stones, another potential side effect.
Avoid Trigger Foods: Limiting consumption of greasy, fried, or spicy foods can reduce heartburn symptoms. Other potential irritants include caffeine, alcohol, and carbonated beverages.
Try Bland Foods: Sticking to simple, bland foods like crackers, toast, pasta, and rice can be easier on the stomach.

Mesalamine Oral Formulations: Administration and GI Effects


Feature	Lialda (Mesalamine) Delayed-Release Tablets	Pentasa (Mesalamine) Extended-Release Capsules	Asacol HD (Mesalamine) Delayed-Release Tablets
Administration	With food	With or without food	On an empty stomach (1 hour before or 2 hours after meals)
Key GI Effects	Nausea, vomiting, abdominal pain, diarrhea	Nausea, vomiting, abdominal pain, diarrhea, gas	Heartburn, indigestion, nausea, abdominal pain
Formulation Note	Designed to release in the colon	Designed to release throughout the digestive tract	Specific timing for release based on stomach pH
Management Tips	Consider dose timing with meal for consistent effect.	Can be sprinkled on soft foods if swallowing is difficult.	Strict adherence to empty stomach instructions is critical for efficacy.

When to Contact Your Doctor

While occasional heartburn from mesalamine may be manageable, certain symptoms warrant a call to your healthcare provider immediately:

Severe or Persistent Symptoms: If heartburn or other GI issues are severe, worsening, or do not improve after trying management techniques.
Signs of Acute Intolerance Syndrome: This rare but serious reaction can present with symptoms resembling an ulcerative colitis flare-up, such as severe cramping, bloody diarrhea, fever, headache, or rash. If you suspect this syndrome, stop the medication and seek medical attention.
Other Serious Side Effects: Fever, chills, unusual bruising or bleeding, chest pain, shortness of breath, or signs of kidney problems (change in urination) are all serious potential side effects that require immediate medical consultation.

Conclusion

For patients with ulcerative colitis, mesalamine is a critical and effective treatment, but it is not without potential side effects. The answer to 'does mesalamine cause heartburn?' is yes, and it is a relatively common occurrence due to the nature of the oral formulations traveling through the digestive tract. By understanding the proper administration of your specific medication, making simple dietary and lifestyle adjustments, and maintaining open communication with your healthcare provider, many patients can effectively manage heartburn and other associated gastrointestinal discomfort. Always discuss your concerns with your doctor to rule out more serious issues and ensure your treatment is as comfortable and effective as possible. A reliable resource for drug information is MedlinePlus.

Frequently Asked Questions

For certain oral mesalamine formulations like Lialda, taking the medication with food is recommended and may help reduce gastrointestinal side effects like heartburn. However, other brands, like Asacol HD, should be taken on an empty stomach. Always follow your doctor's specific instructions for your prescription.

A mesalamine side effect like heartburn is localized discomfort, while a flare-up of ulcerative colitis typically involves symptoms like severe abdominal cramping, bloody diarrhea, and fever. In some rare cases, mesalamine can cause an acute intolerance syndrome that mimics a flare-up, so it's important to consult your doctor to differentiate the cause of your symptoms.

You should not take antacids without first discussing it with your doctor or pharmacist. Some antacids, particularly those containing aluminum and magnesium hydroxide, can interfere with the protective coating of specific mesalamine formulations, like Apriso, and should be avoided or separated by several hours.

For many individuals, mild side effects like heartburn may lessen or resolve on their own within the first few weeks of treatment as the body adjusts. However, if the symptom persists or worsens, you should contact your doctor for further evaluation.

Yes, different oral formulations have different release mechanisms designed to target specific parts of the bowel. This can influence how likely they are to cause upper GI irritation. For example, a delayed-release tablet might have a different effect than an extended-release capsule.

In addition to timing your medication correctly, lifestyle changes can help. Consider eating smaller, more frequent meals, avoiding fatty or spicy foods, staying upright after taking a dose, and incorporating ginger or peppermint tea.

You should contact your doctor if your heartburn is severe, persistent, worsening, or if it is accompanied by other serious symptoms like chest pain, difficulty breathing, bloody stools, or fever.