Asacol (mesalamine) is a first-line, oral 5-aminosalicylic acid (5-ASA) medication specifically engineered for the treatment of mild to moderate ulcerative colitis. Its unique pH-dependent, delayed-release delivery system ensures targeted delivery of the active therapeutic agent directly to the site of colonic inflammation. By concentrating its anti-inflammatory action in the mucosal lining of the colon, Asacol effectively induces and maintains clinical remission, reduces the frequency of disease flares, and promotes endoscopic healing, offering a well-tolerated cornerstone therapy for the long-term management of this chronic condition.

Features

• Active Ingredient: Mesalamine (also known as 5-aminosalicylic acid or 5-ASA).
• Mechanism of Action: A locally acting anti-inflammatory agent with specific topical activity on the colonic mucosa; its exact mechanism is not fully understood but is believed to involve the cyclooxygenase and lipoxygenase pathways, reducing the production of arachidonic acid metabolites, which are mediators of the inflammatory process.
• Delivery System: A unique Eudragit-S coating designed for pH-dependent delayed release. The tablet remains intact until it reaches the terminal ileum and colon (where the pH is 7 or greater), ensuring targeted delivery of mesalamine to the site of disease.
• Dosage Form: Delayed-release oral tablets.
• Available Strengths: 400 mg and 800 mg delayed-release tablets.

Benefits

• Induces Clinical Remission: Effectively reduces the symptoms of active, mild to moderate ulcerative colitis, including diarrhea, rectal bleeding, and abdominal pain.
• Maintains Remission: Significantly reduces the frequency of disease relapse when used as a maintenance therapy, helping patients achieve long periods of symptom-free living.
• Promotes Mucosal Healing: Works at the tissue level to reduce inflammation and facilitate the healing of the damaged colonic mucosa, which is a key treatment goal beyond mere symptom control.
• Targeted Action: The delayed-release design minimizes systemic absorption and maximizes the concentration of the active drug at the primary site of inflammation, enhancing efficacy while limiting whole-body exposure.
• Favorable Safety Profile: As a topical-acting agent, it is generally well-tolerated with a lower incidence of systemic side effects compared to corticosteroids or immunosuppressants.
• Foundation of Therapy: Serves as a first-line and foundational treatment, often allowing for the avoidance of or reduction in the use of more potent immunosuppressive therapies.

Common use

Asacol is indicated for the treatment of active, mild to moderate ulcerative colitis in adult and pediatric patients 5 years of age and older. It is also indicated for the maintenance of remission of ulcerative colitis in adults. Its use is focused on diseases located in the colon, particularly the left colon and rectum, though it is effective for more extensive colitis due to its targeted delivery.

Dosage and direction

For the treatment of active ulcerative colitis:

• Adults: The usual dosage is 2.4 grams to 4.8 grams per day, administered orally in divided doses. A common regimen is two 800 mg tablets three times daily (totaling 4.8 g/day) for 6 weeks.
• Pediatric Patients 5 to 17 years: The dosage is based on body weight, typically ranging from 36 mg/kg to 71 mg/kg per day, administered in two divided doses.

For the maintenance of remission of ulcerative colitis:

• Adults: The usual dosage is 1.6 grams per day, administered orally in divided doses (e.g., two 400 mg tablets twice daily or one 800 mg tablet twice daily).

Administration Instructions:

• Tablets must be swallowed whole and intact. Do not break, crush, or chew the tablets, as this will damage the protective coating and release mesalamine prematurely in the upper GI tract.
• Administer with a full glass of water.
• Doses can be taken with or without food, though consistency is recommended.

Precautions

• Renal Function: Mesalamine has been associated with renal toxicity, including minimal change nephropathy and acute and chronic interstitial nephritis. Assess renal function (e.g., serum creatinine) prior to initiating therapy and periodically during treatment. Exercise caution in patients with pre-existing renal disease.
• Hypersensitivity Reactions: Serious hypersensitivity reactions, including myocarditis, pericarditis, pneumonitis, and rash, have been reported. Discontinue therapy if a hypersensitivity reaction is suspected.
• Hepatic Function: Use with caution in patients with known liver impairment; monitor liver function tests.
• Acute Intolerance Syndrome: A condition resembling a flare of ulcerative colitis (cramping, acute abdominal pain, bloody diarrhea, and sometimes fever, headache, and rash) may occur. Differentiation from a true disease flare is necessary; may require discontinuation.
• Sun Exposure: Mesalamine may increase photosensitivity. Patients should use sun protection measures (sunscreen, protective clothing).
• Phenylalanine Content: The 800 mg tablet contains aspartame, which is a source of phenylalanine (0.56 mg per tablet). This is a consideration for patients with phenylketonuria (PKU).

Contraindications

Asacol is contraindicated in patients with:

• A known hypersensitivity to mesalamine (5-aminosalicylic acid) or any component of the formulation, including salicylates.
• A history of hypersensitivity to sulfasalazine.

Possible side effect

The most common side effects are generally mild and may include:

• Headache
• Abdominal pain/cramping
• Nausea
• Diarrhea
• Flatulence
• Rash
• Fever
• Dizziness

Serious side effects (require immediate medical attention) include:

• Signs of kidney problems (e.g., change in urine output, swelling in feet/ankles, unusual fatigue)
• Signs of a hypersensitivity reaction (e.g., difficulty breathing, chest pain, rash, fever)
• Severe stomach pain, cramping, or bloody diarrhea (may indicate Acute Intolerance Syndrome)
• Signs of liver problems (e.g., yellowing of the skin/eyes, dark urine, severe nausea)
• Signs of pericarditis or myocarditis (e.g., chest pain, shortness of breath, irregular heartbeat)

Drug interaction

• Nephrotoxic Agents: Concurrent use with other agents that may cause renal injury (e.g., NSAIDs, azathioprine, aminoglycoside antibiotics) may increase the risk of renal adverse reactions. Monitor renal function closely.
• 6-Mercaptopurine (6-MP) or Azathioprine: Concomitant use may increase the risk of blood dyscrasias (e.g., leukopenia, neutropenia, thrombocytopenia). Monitor complete blood counts.
• Anticoagulants: Mesalamine may have platelet-inhibiting properties. Use with warfarin or other anticoagulants may potentially increase the risk of bleeding; monitor prothrombin time (PT/INR).

Missed dose

• If a dose is missed, it should be taken as soon as it is remembered.
• However, if it is almost time for the next scheduled dose, the missed dose should be skipped, and the regular dosing schedule resumed.
• Do not double the dose to make up for a missed one.

Overdose

• Symptoms of acute overdose may include severe headache, dizziness, confusion, nausea, vomiting, diarrhea, sweating, tinnitus (ringing in the ears), and hyperventilation.
• There is no specific antidote. Management involves supportive care and monitoring for electrolyte imbalance and renal function. Hemodialysis may be considered in severe cases, although the extent of mesalamine removal is variable.

Storage

• Store at room temperature between 20°C to 25°C (68°F to 77°F); excursions permitted between 15°C and 30°C (59°F and 86°F).
• Keep the bottle tightly closed and stored in a dry place.
• Protect from moisture and light.
• Keep out of reach of children and pets.

Disclaimer

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition or before starting any new treatment. Never disregard professional medical advice or delay in seeking it because of something you have read here. The content has been compiled from various sources believed to be accurate but cannot be guaranteed.

Reviews

• “As a gastroenterologist with over 20 years of practice, Asacol remains a reliable first-line option for my UC patients. Its targeted delivery system provides effective localized control with a safety profile that supports long-term maintenance therapy. I find it particularly useful for achieving and sustaining mucosal healing, which is a critical treatment endpoint.”
• “After being diagnosed with left-sided ulcerative colitis, my doctor started me on Asacol. The first few weeks involved a higher dose to get the flare under control, which it did effectively. I’ve been on a maintenance dose for two years now and have remained in remission. I appreciate that it’s a well-studied medication with a long history of use.”
• “From a clinical trial perspective, Asacol has consistently demonstrated significant efficacy in both induction and maintenance of remission in ulcerative colitis. Its well-defined pharmacokinetics and pharmacodynamics make it a predictable agent within the 5-ASA class. The availability of an 800 mg tablet has improved adherence by reducing pill burden for many patients.”