What are 7 mesalamine side effects to be aware of? (2024)

Key Points

• Mesalamine is a long-term, anti-inflammatory agent that may be used to treat the symptoms of mild to moderate ulcerative colitis and prevent them from recurring. It is available in both oral and rectal formulations.
• Common side effects of mesalamine include stomach problems (such as burping, abdominal pain, constipation, and diarrhea); a headache or dizziness; nasal problems, such as nasal congestion, runny nose, sneezing, or itching; or a rash. For most people, these side effects lessen or go away after a few weeks of treatment.
• More serious side effects with mesalamine are less common or rare, but include allergic reactions, bloody diarrhea or blood in the urine, and an intolerance syndrome.

7 side effects of mesalamine and how to manage them

Let’s look at 7 side effects* of mesalamine that you need to be aware of. Some are common and others are rare. The most common side effects are short-term and only last a few days or weeks. We’ll offer tips on how you can recognize and manage these side effects so you can stay on treatment and live your life.

1. Stomach problems

Stomach (abdominal) side effects with mesalamine are common and occur in approximately one-quarter of patients who take it and may be due to the fact mesalamine acts on cells lining the gastrointestinal tract to reduce inflammation. Burping or belching is the most common side effect, affecting up to 26% of people, followed by abdominal pain (21%), constipation (11%), and indigestion (4%).

Stomach side effects tend to be more common when starting treatment and when your dose is increased too quickly. Because of this, your healthcare provider will slowly increase your dose, until you reach your normal dose. You can take oral mesalamine with or without food.

The good news is that for most people these side effects are mild, temporary, and will not interfere with long-term treatment. They typically subside within a few weeks of starting treatment. In clinical trials, 2.5% of patients stopped taking mesalamine because of abdominal pain.

Tips for managing stomach side effects

Taking mesalamine with food may help with abdominal pain, or changing the form of mesalamine that you take from an oral to a rectal preparation may help. Ask your doctor if this would work for you. Other tips that may help belching, abdominal pain, and indigestion include:

• Eating more slowly
• Consuming smaller meals
• Selecting more bland, low-fat foods (like crackers, pasta, bread, toast and rice)
• Avoiding greasy, fried, or spicy foods
• Drinking plenty of fluids, including water or electrolyte solutions
• Not lying down after eating
• Not wearing belts or clothes that are too restrictive around your stomach area
• Going outside for fresh air or doing some exercise soon after eating
• Drinking ginger and peppermint tea.

If you get constipated, eat more vegetables and whole grains to get more fiber into your diet, and drink plenty of water. Regular exercise also helps.

If none of this advice helps, talk with your healthcare provider.

2. Headache or dizziness

Approximately 10% of people experience headaches and 7% report dizziness with mesalamine. Most people find these symptoms get better after they have taken mesalamine for a few weeks. Rarely, these symptoms have been associated with an increased spinal fluid pressure in the brain or salicylate sensitivity or toxicity.

Tips for managing headache or dizziness

If you experience a headache while taking mesalamine you can:

• Talk to your doctor about the dose you are taking and if a different preparation might help your symptoms.
• Try taking acetaminophen (Tylenol) to relieve a headache
• Keep up your fluids during the day – dehydration can also cause a headache
• Get enough sleep and avoid too much screen time. These can also contribute to a headache
• Practice mindfulness or relaxation techniques.

If you are feeling dizzy, get up slowly when going from a lying or sitting position to standing, so you don’t faint or pass out

• Do not drive, ride a bike, make important decisions, or use tools or machinery if mesalamine makes you feel dizzy during the day
• Do not drink alcohol or take other medications that have drowsiness as a side effect (such as allergy medications) as these will only make your dizziness worse feel

Tell your healthcare provider if mesalamine is still giving you headaches or making you feel dizzy after a few weeks. Call your healthcare provider or seek emergency medical treatment if you have other symptoms in addition to a headache or dizziness such as severe vomiting or abdominal pain, bloody diarrhea, fever, a fast heart rate, confusion, seizures, ringing in your ears, or difficulty with your breathing.

Related Questions

• What can I eat or drink with ulcerative colitis?
• Which is worse: Ulcerative colitis or Crohn's disease?
• What is the life expectancy of someone with ulcerative colitis?

3. Nasal problems

Moderate nasal problems have been reported in people taking oral mesalamine preparations but not rectal preparations.

Rhinitis (nasal congestion, runny nose, sneezing, and itching) was reported by 8% of adults taking mesalamine, and nasopharyngitis (rhinitis symptoms plus a sore throat or coughing) was reported by 15% of children taking mesalamine.

Tips to improve nasal problems

If you experience long-lasting nasal symptoms from mesalamine, talk to your healthcare provider and ask if changing to a rectal preparation is an option for you. Other management tips include:

• Use a saline nasal spray or rinse regularly
• Consider medicated treatments such as acetaminophen or antihistamines (talk to your healthcare provider or pharmacist about which ones to use long-term)
• Keep up your fluids during the day – staying well hydrated can help relieve nasal congestion
• Stop smoking if you smoke
• Consider using a humidifier
• Use an extra pillow to raise your head in bed at night to allow the nasal passages to drain

4. Rash

6% of adults and 5% of children reported a rash with mesalamine use in clinical trials.

Tips for managing a rash

If you or the person you are caring for experiences a rash while taking mesalamine, it is important to talk to your healthcare provider about it. A rash may be a symptom of an allergy or intolerance to mesalamine. Seek emergency help if you have other symptoms along with the rash, such as stomach pain, bloody diarrhea, cramps, fever, or a headache.

5. Allergic reactions

Serious hypersensitivity (allergic) reactions are rare but have been reported with the use of mesalamine; some of these reactions have occurred in people who also experienced a similar reaction to sulfasalazine or to other compounds that contain or are converted to mesalamine.

Mesalamine-induced hypersensitivity reactions may affect your internal organs such as your heart (causing myocarditis or pericarditis), your kidneys (causing nephritis), your liver (causing hepatitis), your lungs (causing pneumonitis), or your blood cells.

Tips for managing an allergic reaction

Stop taking mesalamine and contact emergency medical services right away if you have any of these symptoms:

• Swelling of your face, lips, mouth, tongue, or throat
• Trouble breathing, swallowing, or talking
• Severe rash, hives, or itching
• Very rapid heartbeat or pain in your chest
• Wheezing or feeling of chest tightness
• Fainting or feeling dizzy
• Blistered or peeling skin (with or without a fever).

Do not use mesalamine if you are allergic to it or the inactive ingredients in the preparation or have had an allergic reaction to similar products.

6. Bloody diarrhea or blood in the urine

Bloody diarrhea can be a symptom of mesalamine intolerance syndrome, an exacerbation of ulcerative colitis, or a side effect of mesalamine. Blood in the urine can indicate a kidney stone, and stones of 100% mesalamine content that are radiotransparent and undetectable by standard imaging tests have been reported with mesalamine.

Tips for managing bloody diarrhea or blood in the urine

Stop taking mesalamine and tell your healthcare provider immediately if you experience new or worsening symptoms of bloody diarrhea or blood in the urine. Sometimes these symptoms may be accompanied by cramping, severe abdominal pain, a fever, headache, and rash.

7. Intolerance Syndrome

Mesalamine has been associated with an intolerance syndrome that can be difficult to distinguish from an exacerbation of ulcerative colitis because the symptoms are so similar. Although it is unknown how common this is, it was reported in 3% of patients in clinical trials.

What to do if you suspect you are intolerant to mesalamine

Stop taking mesalamine and tell your healthcare provider immediately if you experience new or worsening symptoms of cramping, severe abdominal pain, or bloody diarrhea. Sometimes these symptoms may be accompanied by a fever, headache, and rash.

* This is not a complete list of side effects. See here for more information.