Sulfasalazine, Uses, Dosage, Side Effects, Interactions, Pregnancy

Sulfasalazine, Uses, Dosage, Side Effects, Interactions, Pregnancy

Sulfasalazine is a synthetic salicylic acid derivative with affinity for connective tissues containing elastin and formulated as a prodrug, antiinflammatory Sulfasalazine acts locally in the intestine through its active metabolites, sulfamide 5-aminosalicylic acid and salicylic acid, by a mechanism that is not clear. It appears inhibit cyclooxygenase and prostaglandin production and is used in the management of inflammatory bowel diseases.

Sulfasalazine a drug that is used in the management of rheumatoid arthritis, ulcerative colitis, and Crohn’s disease, inflammatory bowel diseases.  It is often considered as a first line treatment in rheumatoid arthritis. It is taken by mouth. Its activity is generally considered to lie in its metabolic breakdown product, 5-aminosalicylic acid  released in the colon

Mechanism of Action of Sulfasalazine 

The mode of action of Sulfasalazine or its metabolites, 5-aminosalicylic acid (5-ASA) and sulfapyridine (SP), is still under investigation, but may be related to the anti-inflammatory and/or immunomodulatory properties that have been observed in animal and in vitro models, to its affinity for connective tissue, and/or to the relatively high concentration it reaches in serous fluids, the liver, and intestinal walls, as demonstrated in autoradiographic studies in animals. In ulcerative colitis, clinical studies utilizing rectal administration of Sulfasalazine, SP, and 5-ASA have indicated that the major therapeutic action may reside in the 5-ASA moiety. The relative contribution of the parent drug and the major metabolites in rheumatoid arthritis is unknown.


The purpose of the present study was to determine whether sulfasalazine therapy affected NF-kappaB activation and the expression of pro-inflammatory cytokines in patients with ulcerative colitis. … A total of 38 patients with moderate ulcerative colitis were investigated. Twenty-one patients received sulfasalazine. Seventeen patients did not receive any medication. Biopsy specimens were obtained from the inflamed mucosa and analyzed for NF-kappaB DNA binding activity, NF-kappaBp65/IkappaBalpha protein expression and the levels of pro-inflammatory cytokine mRNA using electrophoretic mobility shift assay, western blot analysis, immunohistochemical staining and reverse transcription-polymerase chain reaction (RT-PCR) analysis, respectively. Increased activation of NF-kappaB and high levels of the expression of interleukin (IL)-1beta mRNA and IL-8 mRNA were detected in biopsy specimens from patients with ulcerative colitis. Therapeutic administration of sulfasalazine effectively downregulated the activation of NF-kappaB and the expression of IL-1beta mRNA and IL-8 mRNA while IkappaBalpha levels were stable. /The authors concluded that/ the therapeutic benefits for ulcerative colitis of sulfasalazine might at least in part be attributed to its ability to inhibit NF-kappaB activation, resulting in the downregulation of pro-inflammatory cytokine mRNA expression.

You Might Also Like   Plantago Gooddingii Seed - Uses, Dosage, Side Effects

Indications of Sulfasalazine 

Contra-Indications of Sulfasalazine 

Patients with intestinal or urinary obstruction, Patients with porphyria as sulfonamides have been reported to precipitate an acute attack, Patients hypersensitive to sulfasalazine, its metabolites, sulfonamides, or salicylates.

  • Severe infection
  • Glucose-6-Phosphate Dehydrogenase Deficiency
  • Porphyria
  • Low Blood Counts due to Bone Marrow Failure
  • Decreased Neutrophils a Type of White Blood Cell
  • Asthma
  • Stomach or Intestine Blockage
  • Liver Problems
  • Kidney disease with reduction in kidney function
  • Urinary Tract Blockage
  • Anemia from Pyruvate Kinase and  Deficiencies
  • Slow Acetylator


Dosage of Sulfasalazine 

Strength: 500 mg, 1000 mg

Rheumatoid Arthritis

  • Delayed-release tablets: 1000 mg orally twice a day

Suggested dosing regimen

  • Week 1: 500 mg orally once a day in the evening
  • Week 2: 500 mg orally twice a day (morning and evening)
  • Week 3: 500 mg orally in the morning and 1000 mg in the evening
  • Week 4: 1000 mg orally twice a day (morning and evening)
  • For maintenance therapy, the dose is 2,000 mg per day taken in 2 evenly divided and evenly spaced doses.

Ulcerative Colitis

  • 3 to 4 g/day orally in evenly divided doses

Crohn’s Disease 

  • 3 to 6 g/day orally in divided doses

juvenile rheumatoid arthritis

  • The maintenance dose is 30–50 mg/kg of body weight per day taken in two evenly divided and evenly spaced doses.
You Might Also Like   Dosage of Botulinum Toxin, Side Effects


  • Initial dose: 500 mg/day, then increased by 500 mg/week
  • Maintenance dose: 1 g twice a day for 1 year; in cases of a new flare, the dose was increased by 500 mg/week up to 3 g/day

 Usual Pediatric Dose

Ulcerative Colitis

6 years or older

  • Initial therapy: 40 to 60 mg/kg/day orally divided into 3 to 6 doses
  • Maintenance therapy: 30 mg/kg/day orally divided into 4 doses

Juvenile Rheumatoid Arthritis

  • 6 years or older: 30 to 50 mg/kg/day orally in 2 equally divided doses
  • Maximum dose: 2 g/day (normally)

Side Effects of Sulfasalazine 

The most common



Drug Interactions of Sulfasalazine 

Sulfasalazine may interact with following drugs, supplyments, & may change the efficacy of drugs

You Might Also Like   Triamcinolone Acetonide; Uses, Dosage, Side Effect, Interactions, Pregnancy

Pregnancy & Lactation of Sulfasalazine 

FDA Pregnancy Category B


This medication should not be used during pregnancy unless the benefits outweigh the risks. If you become pregnant while taking this medication, contact your doctor immediately.


This medication passes into breast milk. If you are a breastfeeding mother and are taking sulfasalazine, it may affect your baby. Talk to your doctor about whether you should continue breastfeeding. This medication is not recommended for children with juvenile rheumatoid arthritis.



If the article is helpful, please Click to Star Icon and Rate This Post!
[Total: 0 Average: 0]

About the author

Translate »