Mesalamine

Ulcerative Colitis Treatment

Mesalamine is a medication used to reduce swelling and irritation in the lining of the large intestine and rectum. It is primarily used for:

• Treating active flares: It helps manage symptoms of mild to moderate ulcerative colitis, such as stomach pain, diarrhea, and rectal bleeding.
• Maintaining remission: Once symptoms are under control, it is often used long-term to prevent the condition from becoming active again.

Targeted Inflammation

Mesalamine may be prescribed for specific types of inflammation depending on where it occurs in the body:

• Proctitis: Inflammation located only in the rectum.
• Proctosigmoiditis: Inflammation in the rectum and the lower part of the colon.
• Distal ulcerative colitis: Inflammation affecting the left side of the colon.

Doctors may prescribe different forms of the medication, such as oral capsules or rectal applications, to ensure the medicine reaches the area where the inflammation is most severe.

Mechanism of Action

Mesalamine, also known as 5-aminosalicylic acid (5-ASA), is an anti-inflammatory drug. While the exact process is not fully understood, it is believed to work topically by coming into direct contact with the inflamed lining of the gastrointestinal tract.

The medication helps control inflammation through several possible actions:

• Blocking inflammatory chemicals: It may inhibit the production of substances like prostaglandins and leukotrienes, which are known to cause swelling and tissue damage in the intestines.
• Reducing oxidative stress: It may act as an antioxidant, helping to neutralize free radicals that contribute to inflammation.

By decreasing the inflammation in the colon and rectum, mesalamine helps reduce symptoms such as stomach pain, diarrhea, and rectal bleeding. It is used both to treat active flare-ups and to help maintain remission by preventing the inflammation from returning.

Common Side Effects

Many people using mesalamine experience mild side effects. These may include:

• Headache
• Nausea, vomiting, or stomach pain
• Gas, bloating, or diarrhea
• Constipation
• Dizziness or tiredness
• Back or joint pain
• Itching or mild skin rash
• Flu-like symptoms, such as fever or sore throat

If you are using rectal forms of this medication, you may also experience rectal pain, burning, or a frequent urge to have a bowel movement.

Serious Side Effects

Contact a healthcare provider immediately if you experience any of the following serious symptoms:

• Acute intolerance syndrome: This includes severe stomach pain, cramping, bloody diarrhea, fever, headache, and rash.
• Kidney problems: Signs may include increased thirst, swelling of the feet or lower legs, or a change in the amount or color of urine.
• Liver problems: Symptoms include yellowing of the eyes or skin, dark urine, severe fatigue, or pain in the upper right stomach area.
• Heart problems: Chest pain, shortness of breath, or a fast or irregular heartbeat.
• Severe skin reactions: Blistering, peeling, or a red rash that spreads.
• Allergic reactions: Hives, difficulty breathing, or swelling of the face, lips, or tongue.

Kidney Function

Mesalamine has been associated with kidney impairment, including kidney failure and inflammation. Healthcare providers typically evaluate kidney function before starting treatment and monitor it periodically during therapy.

Acute Intolerance Syndrome

Some individuals experience a reaction called acute intolerance syndrome, which can be difficult to distinguish from a flare-up of inflammatory bowel disease. Symptoms may include abdominal pain, cramping, bloody diarrhea, fever, headache, and rash. If these symptoms occur, the medication is usually discontinued immediately.

Allergic Reactions

Serious hypersensitivity reactions, including severe skin conditions like Stevens-Johnson syndrome, have been reported. This medication is contraindicated for individuals with a known allergy to salicylates, such as aspirin, or other aminosalicylates.

Liver Health

Caution is advised for patients with pre-existing liver disease, as there have been reports of liver failure in people using mesalamine.

Other Precautions

• Photosensitivity: People with existing skin conditions, such as eczema, may be more sensitive to sunlight while taking this drug.
• Kidney Stones: There have been reports of kidney stones forming during treatment. Maintaining adequate fluid intake is often recommended.
• Drug Interactions: Using mesalamine with certain other medications, such as azathioprine or 6-mercaptopurine, may increase the risk of blood-related side effects.

Pregnancy

Mesalamine is known to cross the placental barrier. While animal studies using high doses have not shown a significant risk of harm to the fetus, there are limited well-controlled studies in pregnant humans. Because animal reproduction studies are not always predictive of human response, mesalamine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.

Breastfeeding

Mesalamine and its primary metabolite are excreted in human breast milk. There have been reports of diarrhea in infants who are breastfed by individuals taking mesalamine. If you are breastfeeding or planning to breastfeed, it is important to discuss the risks and benefits with your healthcare provider. If you continue to use this medication while breastfeeding, monitor your infant closely for changes in bowel movements, such as diarrhea.

Oral Formulations

Mesalamine is commonly taken by mouth in forms designed to bypass the stomach and release the medication in the intestines. These include:

• Delayed-release tablets
• Delayed-release capsules
• Extended-release capsules

Rectal Formulations

For inflammation located in the lower part of the colon or rectum, mesalamine may be administered rectally. These forms include:

• Rectal suppositories
• Rectal suspension (enema)

The specific form prescribed often depends on the location and severity of the inflammation within the digestive system.

FDA Approval and Indications

Mesalamine is approved by the U.S. Food and Drug Administration (FDA) for the treatment of mildly to moderately active ulcerative colitis. It is also indicated for the maintenance of remission in patients with ulcerative colitis. The specific approved uses and age groups may vary depending on the formulation and the manufacturer.

Approved Formulations

The FDA has approved mesalamine in several delivery formats to target inflammation in different areas of the gastrointestinal tract:

• Oral formulations: These include delayed-release tablets, delayed-release capsules, and extended-release capsules.
• Rectal formulations: These include suppositories and rectal suspensions (enemas).

Safety and Regulatory Monitoring

Mesalamine does not currently have any boxed warnings or Risk Evaluation and Mitigation Strategies (REMS) requirements. However, the FDA requires labeling to include warnings regarding the risk of renal impairment. Healthcare providers are generally advised to assess kidney function before starting treatment and periodically during therapy. Other regulatory warnings include mesalamine-induced acute intolerance syndrome, which can cause symptoms similar to an ulcerative colitis flare, and potential hypersensitivity reactions.

Formulation and Pricing

Mesalamine is available in several different forms, including oral delayed-release tablets, extended-release capsules, rectal suppositories, and rectal enemas. The price often depends on the specific delivery system required for the condition. Oral formulations designed for targeted release in the colon may have different price points than rectal applications.

Generic Availability

Generic versions are available for many mesalamine products, such as those equivalent to Lialda or Canasa. Opting for a generic version typically reduces the out-of-pocket expense. However, not all brand-name formulations have a generic equivalent, and some newer or specialized delivery systems may only be available as higher-priced brand-name drugs.

Insurance and Assistance

Most health insurance plans and Medicare Part D provide coverage for mesalamine, though the specific cost to the patient depends on the plan's formulary. Generic versions are usually placed in lower-cost tiers with smaller copayments. For patients without insurance or those with high deductibles, some manufacturers offer savings cards or patient assistance programs for brand-name products.