Brand Name : SALAZO
Generic Name : Sulfasalazine
Preparation : 500 mg Enteric Coated Tablet
Pharmacological Categories : DMARD (Disease Modifying Antirheumatoid Drug) / Anti-inflammatory Agent

Mechanism of Action (MOA)
SALAZO (Sulfasalazine) is a prodrug that is hydrolyzed by colonic bacteria into 5-aminosalicylic acid (5-ASA; Mesalamine) and sulfapyridine. 5-aminosalicylic acid is an inhibitor of prostaglandin biosynthesis. Moreover, sulfasalazine and / or its metabolites inhibit the release of inflammatory cytokines and TNF-α locally on the bowel. Also, SALAZO has beneficial systemic immunosuppressant effect.


  • Bioavailability : Under 15% (sulfasalazine); 60% (sulfapyridine); 10-30% (5-ASA)
  • Peak Plasma Time : 6 hours (sulfasalazine); 10 hours (sulfapyridine and 5-ASA)
  • Protein Binding : More than 99% to albumin (sulfasalazine); 70% (sulfapyridine)
  • Metabolism : Colonic bacteria
  • Elimination Half-life : 10.4 to 14.8 hours (sulfapyridine)
  • Excretion : Urine (systematically absorbed sulfapyridine and 5-ASA); faeces (majority of 5-ASA)

Indications and Dosage

  • Ulcerative Colitis
    Initially : Six to eight tablets of SALAZO per day in evenly divided doses with intervals no more than 8 hours; may initiate with two to four tablets of SALAZO per day to reduce gastrointestinal intolerance
    Maintenance : Four tablets of SALAZO per day orally in evenly divided doses
  • Rheumatoid Arthritis
    Initially :
    1st week : One tablet of SALAZO once daily
    2nd week : One tablet of SALAZO twice daily
    3rd week : One tablet of SALAZO in the morning followed by two tablets of SALAZO in the evening
    4th week : Two tablets of SALAZO three times a day
    Daily dose may be increased up to SALAZO 3000 mg per day if clinical response is inadequate after 12 weeks
  • Crohn’s Disease (Off-label) : Six to twelve tablets of SALAZO per day in divided doses
    Pediatric (safety and efficacy has not been established in children below 6 years of age)
  • Ulcerative Colitis
    6 years or older
    Initial : SALAZO 40 to 60 mg per kg per day divided every 4 to 8 hours
    Maintenance : SALAZO 30 mg per kg per day divided every 6 hour
  • Juvenile Rheumatoid Arthritis
    6 years or older : SALAZO 30 to 50 mg per kg per day in 2 equally divided doses
    Maximum dose : SALAZO 2 gm per day

Administration : Take after meals. Administer in equally divided doses

Side Effects
GREATER THAN 10 % : Anorexia, headache, nausea, vomiting, gastric distress, apparently reversible oligospermia
RARE (LESS THAN 1 %) : Skin rash, pruritus, urticaria, fever, Heinz body anemia, hemolytic anemia, cyanosis
POST MARKETING REPORTS : Pseudomononucleosis, myocarditis, hepatotoxicity, elevated liver function tests, jaundice, cholestatic jaundice, cirrhosis, hepatitis, cholestasis and possible hepatocellular damage including liver necrosis and liver failure, Kawasaki-like syndrome, anaphylaxis, folate deficiency, nephrolithiasis, oropharyngeal pain, angioedema, purpura, pallor

Hypersensitivity to sulfasalazine or its metabolites, sulfonamides, or salicylates; intestinal or urinary tract obstruction; porphyria

Warnings / Precautions

  • Caution in severe allergy or bronchial asthma.
  • Blood dyscrasias and serious infections have been reported, including fatal sepsis, pneumonia and some infections were associated with agranulocytosis, neutropenia, or myelosuppression.
  • Serious skin reactions have been reported such as exfoliative dermatitis, Stevens-Johnson syndrome and toxic epidermal necrolysis.
  • Severe hypersensitivity has been reported, including hepatitis, nephritis, myocarditis, mononucleosis like syndrome, hematological abnormalities and pneumonitis.
  • Caution in anemia, gout, hepatic / renal impairment, hypochlorhydria, hypoprothrombinemia, thyrotoxicosis, vitamin K deficiency.
  • Ensure adequate hydration to prevent crystalluria.
  • May cause orange discoloration of the urine or skin.
  • Some reports of bloody stools or diarrhoea in human milk fed infants of mothers taking sulfasalazine

Drug Interactions

  • Sulfasalazine may potentiate the effects of coumarin anticoagulants.
  • Sulfasalazine may potentiate the hypoglycemic effects of tolbutamide and chlorpropamide when used together.
  • Concomitant use of anti-infectives may alter the action of sulfasalazine by altering intestinal flora and its metabolism.
  • Sulfasalazine possibly decrease the absorption of digoxin.
  • Sulfasalazine inhibits the absorption and metabolism of folic acid.
  • Concomitant use of sulfasalazine and iron causes formation of iron chelates altering absorption and distribution of sulfasalazine.

Pregnancy Category : B but becomes D if used for prolonged periods or near term; increased potential for kernicterus in the newborn

SALAZO 500 mg : A box of 10 blisters, each blister of 10 tablets