Generic Pentasa ( Mesalamine )

Buy cheap Generic Pentasa (Mesalamine) without dr prescription at Canadian Pharmacy

Pentasa (Mesalamine 400 mg): Comprehensive Patient Information for Canada

Basic Product Information

Mechanism of Action

In simple terms: Pentasa is an anti-inflammatory medication used to treat inflammatory bowel disease, particularly ulcerative colitis. It works directly on the lining of the intestine to reduce inflammation. The exact way it works is not fully understood, but it is believed to block the production of substances in the body that cause inflammation. Because it acts locally in the gut, it has fewer systemic side effects than some other anti-inflammatory drugs.

For specialists: The mechanism of action of mesalamine is not fully understood, but it appears to be topical rather than systemic, acting on colonic epithelial cells to diminish inflammation. Mucosal production of arachidonic acid metabolites, both through the cyclooxygenase pathways (prostanoids) and through the lipoxygenase pathways (leukotrienes and hydroxyeicosatetraenoic acids), is increased in patients with chronic inflammatory bowel disease. It is possible that mesalamine diminishes inflammation by blocking cyclooxygenase and inhibiting prostaglandin production in the colon. Proposed mechanisms also include activation of the gamma form of peroxisome proliferator-activated receptors (PPAR-γ) and inhibition of nuclear factor-kappa B (NF-κB) in the intestinal mucosa. Mesalamine has in vitro and in vivo pharmacological effects that inhibit leucocyte chemotaxis, decrease cytokine and leukotriene production, and scavenge for free radicals.

Pharmacokinetics

• Absorption: Pentasa is an ethylcellulose-coated, controlled-release formulation of mesalamine designed to release therapeutic quantities of mesalamine throughout the gastrointestinal tract. Based on urinary excretion data, 20% to 30% of the mesalamine in Pentasa is absorbed. Plasma mesalamine concentration peaked at approximately 1 mcg/mL 3 hours following a 1-g Pentasa dose and declined in a biphasic manner. The bioavailability of mesalamine after oral administration is estimated to be about 30% based on urinary excretion data in healthy subjects, with maximum plasma concentration reached 1 to 6 hours after dosing.
• Metabolism: Mesalamine is metabolized both locally in the intestinal mucosa and systemically in the liver to N-acetyl-mesalamine (acetyl-mesalamine), mainly via N-acetyltransferase 1. Some acetylation also occurs via colon bacteria. Acetylation appears to be independent of the patient's acetylator phenotype. Acetyl-mesalamine is considered clinically and toxicologically inactive.
• Elimination: Both mesalamine and acetyl-mesalamine are excreted via urine and feces. Urinary excretion consists mostly of acetyl-mesalamine. The mean terminal half-life of mesalamine following intravenous administration is approximately 42 minutes. Because of the continuous release and absorption of mesalamine from Pentasa throughout the gastrointestinal tract, the true elimination half-life cannot be determined after oral administration. The mean elimination half-life at steady state for both mesalamine and N-acetyl-5-ASA is 7 to 12 hours.
• Onset of Action: Symptomatic improvement in ulcerative colitis is typically observed within 1 to 2 weeks, but full therapeutic effect may take up to 6 weeks.
• Duration of Action: The anti-inflammatory effect is maintained with continued daily dosing. Mesalamine is used for both induction of remission and maintenance therapy.

Uses in Daily Life and Best Practice Advice

Mesalamine is prescribed in Canada for the treatment of inflammatory bowel disease. Your physician will determine the appropriate use and dose based on your specific condition and medical history.

• Typical Uses: Pentasa is indicated for the induction of remission and for the treatment of patients with mildly to moderately active ulcerative colitis. It is also used for the maintenance of remission of ulcerative colitis.
• Administration: Swallow the tablet whole with a full glass of water. Do not chew, crush, or break the tablet, as this will destroy the delayed-release coating and reduce effectiveness. The tablet should be taken with food.
• Monitoring: Your physician will monitor your response to treatment and may perform periodic blood tests to check kidney and liver function. Kidney function should be evaluated prior to initiation of Pentasa and periodically while on therapy. If your symptoms do not improve or worsen, consult your physician.
• Do Not Stop Without Medical Advice: Do not stop taking mesalamine without consulting your physician, as this may lead to a flare-up of your condition.

Morning vs. Evening Dosing

Mesalamine is typically taken three times daily or as directed by your physician. The dosing schedule depends on the specific product and the indication being treated. For enteric-coated 400 mg tablets, the usual dosing is two tablets three times daily for active disease and one tablet three times daily for maintenance. There is no specific clinical recommendation for morning versus evening dosing, but taking it with meals helps with consistency and reduces the risk of gastrointestinal upset. Always follow the schedule recommended by your physician.

• Divided Dosing: When taken three times daily, the doses are usually taken at mealtimes.
• Consistency: Take mesalamine at the same times each day to ensure consistent effects.
• Missed Dose: If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take two doses at the same time.
• Professional Guidance: Your healthcare provider may adjust the frequency and timing based on your response to treatment and other medications.

Administration With or Without Food

Mesalamine should be taken with food. Taking it with a meal helps reduce the risk of stomach upset and may improve absorption consistency. The delayed-release coating is designed to release the medication in the colon, and food can affect the transit time through the gastrointestinal tract.

• Take the tablet with a meal or snack.
• Swallow the tablet whole with a full glass of water.
• Do not chew, crush, or break the tablet, as this will destroy the delayed-release coating.
• If you have difficulty swallowing tablets, consult your pharmacist about alternative formulations of mesalamine that may be easier to take.
• Drink an adequate amount of fluids during treatment, as cases of kidney stones have been reported with mesalamine use.

Interaction Warnings

Indications for Mesalamine

"Off-label" means use outside the official approved indication, usually based on current medical guidelines and scientific evidence.

Dosing According to Clinical Indication

Doses should always be adjusted according to the advice of your physician and depending on your health condition. Health Canada has not authorized an indication for pediatric use, but pediatric dosing based on weight is used in clinical practice. The dosage can be adjusted in accordance with the response to treatment.

Side Effects and Safety Profile

Guidelines for Correct Use

• Take mesalamine exactly as prescribed by your physician. Do not change your dose without medical advice.
• Swallow the tablet whole with a full glass of water. Do not chew, crush, or break the tablet, as this will destroy the delayed-release coating.
• Take the tablet with food to reduce the risk of stomach upset.
• Do not take antacids within 2 hours of taking mesalamine.
• Do not stop taking this medication without consulting your physician, as this may lead to a flare-up of your condition.
• Keep all medical appointments for monitoring of kidney function, liver function, and blood counts.
• Inform every healthcare provider (including dentists, surgeons, and pharmacists) that you are taking mesalamine.
• If you are pregnant, planning to become pregnant, or breastfeeding, consult your physician before use.
• If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose. Do not double the dose.
• Store at room temperature in a dry place. Keep out of reach of children.

Alternative Treatment Options

• Sulfasalazine (Salazopyrin): A prodrug of mesalamine combined with sulfapyridine. It is effective for ulcerative colitis and Crohn's disease but has a higher incidence of side effects, particularly gastrointestinal intolerance and hypersensitivity reactions. Requires folic acid supplementation.
• Balsalazide (Colazal): A prodrug of mesalamine linked to an inert carrier. It delivers mesalamine to the colon and is effective for mildly to moderately active ulcerative colitis. May be better tolerated than sulfasalazine.
• Olsalazine (Dipentum): A dimer of two mesalamine molecules. It is effective for maintenance of remission of ulcerative colitis but can cause diarrhea in a significant proportion of patients.
• Corticosteroids (e.g., prednisone, budesonide): Used for moderate to severe flares of ulcerative colitis and Crohn's disease. Effective for rapid induction of remission but not suitable for long-term maintenance due to significant side effects.
• Immunomodulators (e.g., azathioprine, 6-mercaptopurine, methotrexate): Used for maintenance of remission in patients who do not respond adequately to mesalamine or who have moderate to severe disease.
• Biologic Agents (e.g., infliximab, adalimumab, vedolizumab, ustekinumab): Targeted therapies for moderate to severe inflammatory bowel disease that has not responded to conventional treatments.

Comparison: Mesalamine is the first-line therapy for mild to moderately active ulcerative colitis and for maintenance of remission. It is distinguished from sulfasalazine by its better tolerability profile, as it does not contain the sulfapyridine component that is responsible for many of the adverse effects of sulfasalazine. Mesalamine is available in multiple formulations that target different parts of the gastrointestinal tract, allowing for tailored therapy. For patients who cannot tolerate mesalamine, balsalazide or olsalazine may be considered. Corticosteroids are reserved for more severe flares and are not used for long-term maintenance. Your physician will determine the best option for your specific condition.

Legal Status, Registration, and Coverage in Canada

• Registration: Mesalamine is authorized for sale in Canada by Health Canada as a prescription drug. Pentasa is available as prolonged-release tablets (500 mg and 1 g), prolonged-release granules, rectal suspension, and suppositories. Generic mesalamine 400 mg enteric-coated tablets are available from Teva Canada (TEVA-5 ASA, DIN 02171929) and other manufacturers. The brand-name Asacol 400 mg tablet (DIN 01997580) was cancelled post-market in 2020.
• Prescription Status: Prescription only in Canada.
• Coverage: Coverage varies by province, territory, and private insurance plan. In Quebec, Pentasa 500 mg tablets are listed on the RAMQ formulary at $0.5569 per tablet, and Pentasa 1 g tablets are listed at $1.1138 per tablet. In Alberta, Pentasa 500 mg sustained-release tablets are listed at $0.5569 per tablet, and Pentasa 1 g rectal suppositories are listed at $1.6000 per suppository. In Ontario, Pentasa 500 mg delayed-release tablets are listed at $0.7770 per tablet, and Pentasa 1 g/100 mL enema is listed at $6.86 per unit. Generic formulations such as TEVA-5 ASA 400 mg are listed on the RAMQ formulary at $0.3111 per tablet.
• Pharmacovigilance: Adverse reactions should be reported to Health Canada's MedEffect Canada program.

Recent Research and Clinical Guidelines (2022–2026)

• The 2025 German clinical practice guidelines recommend mesalamine ≥1000 mg/day as a suppository for mild to moderately active proctitis. For maintenance of remission in ulcerative colitis, mesalamine is recommended as the primary therapy, and remission-maintaining therapy with mesalamine should be continued for at least 2 years if effective.
• Current clinical practice guidelines recommend combination therapy with oral mesalamine ≥2.4 g/day plus topical mesalamine ≥1 g/day as the most effective first-line approach for mild to moderate ulcerative colitis flares, superior to either agent alone.
• Pentasa is licensed for ulcerative colitis patients only in some jurisdictions, while other mesalamine formulations such as Salofalk may also be licensed for Crohn's disease.
• The MHRA Drug Safety Update from December 2025 highlighted a potential association between mesalamine and idiopathic intracranial hypertension.
• Research continues to explore the role of mesalamine in combination with other agents for inflammatory bowel disease, as well as its potential role in preventing colorectal cancer in patients with ulcerative colitis. Experimental models and patient biopsies support that mesalamine prevents colitis-associated colorectal cancer through downregulation of both inflammation-dependent and inflammation-independent signaling pathways.
• A drug shortage of TEVA-5 ASA 400 mg tablets was reported in October 2025 and again in January 2026 due to manufacturing disruptions. The shortage was resolved with an anticipated end date in early 2026.

Availability and Supply in Canada

Prices and availability may vary by province, territory, and pharmacy. A drug shortage for TEVA-5 ASA 400 mg was reported in 2025 and 2026 but has since been resolved. Generic mesalamine formulations are widely available in Canada and are generally more affordable than brand-name products. Check with your local pharmacy for current pricing and availability.

Frequently Asked Questions (FAQ)

1. Is Pentasa available in Canada?
   Yes. Pentasa is available in Canada by prescription from Ferring Inc. in several formulations, including prolonged-release tablets (500 mg and 1 g), prolonged-release granules, rectal suspension, and suppositories. Generic mesalamine 400 mg enteric-coated tablets are also available from Teva Canada and other manufacturers.
2. What is Pentasa used for?
   Pentasa is used for the induction of remission and for the treatment of mildly to moderately active ulcerative colitis in adult patients. It is also used for the maintenance of remission of ulcerative colitis.
3. What is the difference between Pentasa 400 mg and 500 mg?
   Pentasa 400 mg is available as a generic enteric-coated tablet (e.g., TEVA-5 ASA). Pentasa 500 mg is a prolonged-release tablet manufactured by Ferring. The 400 mg strength is often used for dose titration and is dosed three times daily, while the 500 mg and 1 g strengths are prolonged-release formulations that may be dosed differently. Your physician will determine the appropriate strength and formulation for your condition.
4. How long does mesalamine take to work?
   Symptomatic improvement in ulcerative colitis is typically observed within 1 to 2 weeks, but full therapeutic effect may take up to 6 weeks. It is important to continue taking the medication as prescribed even if you start to feel better.
5. Can I take Pentasa with food?
   Yes. Mesalamine should be taken with food to reduce the risk of stomach upset. Swallow the tablet whole with a full glass of water. Do not chew, crush, or break the tablet.
6. What should I do if I miss a dose of Pentasa?
   If you miss a dose, take it as soon as you remember. If it is almost time for your next dose, skip the missed dose and continue with your regular schedule. Do not take two doses at the same time.
7. Can I stop taking Pentasa if I feel better?
   No. Do not stop taking Pentasa without consulting your physician. Stopping the medication can lead to a flare-up of your condition. Your physician will advise you on the appropriate duration of treatment.
8. What are the serious side effects of mesalamine?
   Serious side effects include kidney problems (including interstitial nephritis and renal failure), severe blood disorders, severe skin reactions, and acute mesalamine intolerance (which may present as worsening of ulcerative colitis with abdominal cramps, fever, severe headache, and rash). Seek immediate medical attention if you experience any of these symptoms.
9. Is mesalamine safe during pregnancy?
   Mesalamine should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus. Mesalamine crosses the placental barrier. A single case of neonatal renal failure has been reported after high-dose, long-term maternal use. Consult your physician if you are pregnant or planning to become pregnant.
10. Is mesalamine safe during breastfeeding?
    Mesalamine is excreted in breast milk in small amounts. Reports of diarrhea in breastfed infants exist. Monitor the infant for changes in intestinal activity. If diarrhea develops, breastfeeding should be discontinued. Consult your physician before use.
11. Are there generic versions of mesalamine available in Canada?
    Yes. Generic mesalamine 400 mg enteric-coated tablets are widely available in Canada from multiple manufacturers, including Teva Canada, Pendopharm, Sanis Health, and others. Generic versions are generally more affordable than brand-name products.

How to buy Generic Pentasa without rx in Canada.