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Medically reviewed by Last updated on May 17, 2020.


(bal SAL a zide)

Index Terms

  • Balsalazide Disodium

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product

Capsule, Oral, as disodium:

Colazal: 750 mg

Generic: 750 mg

Tablet, Oral, as disodium:

Giazo: 1.1 g [DSC]

Brand Names: U.S.

  • Colazal
  • Giazo [DSC]

Pharmacologic Category

  • 5-Aminosalicylic Acid Derivative
  • Anti-inflammatory Agent


Balsalazide is a prodrug, converted by bacterial azoreduction to 5-aminosalicylic acid (mesalamine, active), 4-aminobenzoyl-β-alanine (inert), and their metabolites. 5-aminosalicylic acid may decrease inflammation by blocking the production of arachidonic acid metabolites topically in the colon mucosa.


Very low and variable; in children, reported systemic absorption of 5-ASA (active) lower than adults (Cmax: 67% lower, AUC: 64% lower); time to steady ~2 weeks in pediatric and adult patients


Azoreduced in the colon to 5-aminosalicylic acid (active), 4-aminobenzoyl-β-alanine (inert), and N-acetylated metabolites


Feces (65% as 5-aminosalicylic acid, 4-aminobenzoyl-β-alanine, and N-acetylated metabolites); urine (<16% as N-acetylated metabolites); Parent drug: Urine or feces (<1%)

Time to Peak

Balsalazide: Capsule: 1 to 2 hours; Tablet: 0.5 hours

Half-Life Elimination

Primary effect is topical (colonic mucosa); therapeutic effect appears not to be influenced by the systemic half-life of balsalazide (1.9 hours) or its metabolites (5-ASA [9.5 hours], N-Ac-5-ASA [10.4 hours])

Protein Binding

Balsalazide: ≥99%

Special Populations Note

Ulcerative colitis: May have increased AUC.

Use: Labeled Indications

Ulcerative colitis: Treatment of mildly- to moderately-active ulcerative colitis

Limitations of use: Efficacy of Giazo has not been demonstrated in females.

Off Label Uses

Ulcerative colitis, remission maintenance

Data from a meta-analysis of randomized, double-blind, placebo controlled trials support the use of balsalazide for 6 to 12 months for remission maintenance in ulcerative colitis [Ford 2011].

Based on the American Gastroenterological Association guidelines on the management of mild to moderate ulcerative colitis, balsalazide is an option for remission maintenance in patients with extensive mild to moderate ulcerative colitis; however, evidence was low quality due to imprecision and indirectness.


Hypersensitivity to balsalazide or its metabolites, salicylates, or any component of the formulation

Dosing: Adult

Note: Giazo has been discontinued in the United States for more than 1 year.

Ulcerative colitis, remission induction: Oral:

Capsule: 2.25 g 3 times daily for 8 to 12 weeks.

Tablet: Males: 3.3 g twice daily for up to 8 weeks.

Ulcerative colitis, remission maintenance (off-label use): Capsule: 1.5 or 3 g twice daily for 6 to 12 months (Ford 2011).

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Note: Giazo has been discontinued in the US for >1 year.

Ulcerative colitis:

Children ≥5 years and Adolescents ≤17 years: Oral: Capsules:

2.25 g (three 750 mg capsules) 3 times daily (total daily dose: 6.75 g/day) for up to 8 weeks.


750 mg (one capsule) 3 times daily (total daily dose: 2.25 g/day) for up to 8 weeks.

Note: Multicenter, double-blind clinical trial in pediatric patients (n=68, ages 5 to 17 years) showed clinical improvement in both treatment groups (2.25 g/day and 6.75 g/day); there was not a statistical difference in clinical response between the two treatment groups (Quiros 2009).

Adolescents ≥18 years: Oral:

Capsule: 2.25 g (three 750 mg capsules) 3 times daily (total daily dose: 6.75 g/day) for up to 8 to 12 weeks.

Tablet: Males: 3.3 g (three 1.1 g tablets) twice daily (total daily dose: 6.6 g/day) for up to 8 weeks.


Oral: May administer with or without food. Administer with an adequate amount of fluid.

Capsule: May be swallowed whole or may be opened and sprinkled on applesauce. Applesauce mixture may be chewed; swallow immediately, do not store mixture for later use. When sprinkled on food, may cause staining of teeth or tongue.

Dietary Considerations

Some products may contain sodium.


Store at controlled room temperature of 20°C to 25°C (68°F to 77°F); excursions permitted to 15°C to 30°C (59°F to 86°F).

Drug Interactions

Cardiac Glycosides: 5-Aminosalicylic Acid Derivatives may decrease the serum concentration of Cardiac Glycosides. Monitor therapy

Heparin: 5-Aminosalicylic Acid Derivatives may enhance the adverse/toxic effect of Heparin. Specifically, the risk for bleeding/bruising may be increased. Monitor therapy

Heparins (Low Molecular Weight): 5-Aminosalicylic Acid Derivatives may enhance the adverse/toxic effect of Heparins (Low Molecular Weight). Specifically, the risk for bleeding/bruising may be increased. Monitor therapy

Nonsteroidal Anti-Inflammatory Agents: May enhance the nephrotoxic effect of 5-Aminosalicylic Acid Derivatives. Monitor therapy

Thiopurine Analogs: 5-Aminosalicylic Acid Derivatives may decrease the metabolism of Thiopurine Analogs. Monitor therapy

Varicella Virus-Containing Vaccines: 5-Aminosalicylic Acid Derivatives may enhance the adverse/toxic effect of Varicella Virus-Containing Vaccines. The primary concern is the potential development of Reye's Syndrome, a condition that has been associated with the use of salicylates in children with varicella infections. Management: Avoid administration of salicylates for at least 6 weeks after adminstration of a varicella virus-containing vaccine. Consider therapy modification

Adverse Reactions


Central nervous system: Headache (children: 15%; adults: 8%)

Gastrointestinal: Abdominal pain (children: 12% to 13%; adults: ≤6%)

1% to 10%:

Central nervous system: Fatigue (children: 4%; adults: ≤2%), insomnia (adults: 2%)

Gastrointestinal: Vomiting (children: 10%; adults: ≤4%), diarrhea (children: 9%; adults: ≤5%), exacerbation of ulcerative colitis (children: 6%; adults: 1%), nausea (adults: 5%; children: 4%), hematochezia (children: 4%), stomatitis (children: 3%), anorexia (adults: 2%), dyspepsia (adults: 2%), flatulence (adults: ≤2%), abdominal cramps (adults: 1%), constipation (adults: ≤1%), xerostomia (adults: ≤1%)

Genitourinary: Urinary tract infection (adults: 1% to 4%), dysmenorrhea (children: 3%)

Hematologic & oncologic: Anemia (4%)

Neuromuscular & skeletal: Arthralgia (adults: ≤4%), musculoskeletal pain (adults: 2%), myalgia (adults: ≤1%)

Respiratory: Pharyngitis (children: 6%; adults: 2%), flu-like symptoms (children: 4%; adults: 1%), respiratory infection (adults: ≤4%), cough (children: 3%; adults: 2%), pharyngolaryngeal pain (adults: 4%, children: 3%), rhinitis (adults: 2%)

Miscellaneous: Fever (children: 6%; adults: 2%)

<1%, postmarketing, and/or case reports: Alopecia, back pain, bowel urgency, bronchopneumonia, cholestatic jaundice, dizziness, dyspnea, edema, erythema nodosum, facial edema, fecal impaction, gastroenteritis, gastroesophageal reflux disease, hepatic cirrhosis, hepatic failure, hepatic injury, hepatic necrosis, hepatotoxicity, hyperbilirubinemia, hypersensitivity reaction, increased blood pressure, increased heart rate, increased liver enzymes, increased serum AST, interstitial nephritis, jaundice, Kawasaki-like syndrome, lethargy, malaise, myocarditis, pain, pancreatitis, pericarditis, pleural effusion, pneumonia (with and without eosinophilia), pruritus, renal failure, skin rash, vasculitis


Concerns related to adverse effects:

• Colitis: Symptomatic worsening of ulcerative colitis may occur following initiation of treatment.

• Intolerance syndrome: May cause an acute intolerance syndrome (cramping, acute abdominal pain, bloody diarrhea; sometimes fever, headache, rash); discontinue if this occurs.

• Nephrolithiasis: Cases of nephrolithiasis (including stones with 100% mesalamine content) have occurred with mesalamine use. Stones may be radiotransparent and undetectable by standard imaging. Ensure patients are adequately hydrated during therapy.

• Staining: May cause staining of teeth or tongue if capsule is opened and sprinkled on food.

Disease-related concerns:

• Hepatic impairment: Use caution in patients with hepatic dysfunction; hepatic failure has been observed with other mesalamine (5-aminosalicylic acid) products.

• Pyloric stenosis: Use with caution in patients with pyloric stenosis; prolonged gastric retention may occur and delay release of drug in the colon.

• Renal impairment: Use with caution in patients with renal impairment; renal toxicity has been observed with other mesalamine (5-aminosalicylic acid) products.

Monitoring Parameters

Improvement or worsening of symptoms; renal function (baseline, within first 6 months of initiation, then annually thereafter) (Hanauer 2008); liver function tests (in patients with liver disease)

Pregnancy Considerations

Mesalamine (5-aminosalicylic acid) is the active metabolite of balsalazide; mesalamine is known to cross the placenta. Refer to the mesalamine monograph for additional information.

Patient Education

What is this drug used for?

• It is used to treat ulcerative colitis.

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

• Headache

• Stomach pain or diarrhea

• Upset stomach or throwing up

• Nose or throat irritation

• Common cold symptoms

• Joint pain

• Feeling tired or weak

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

• Liver problems like dark urine, feeling tired, not hungry, upset stomach, stomach pain, light-colored stools, throwing up, or yellow skin or eyes

• Kidney problems like unable to pass urine, blood in the urine, change in amount of urine passed, or weight gain

• Kidney stones like back pain, belly pain, or blood in the urine

• Ulcerative colitis like severe stomach pain or cramps; bloody stools; fever; headache; or rash

• Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.

Note: This is not a comprehensive list of all side effects. Talk to your doctor if you have questions.

Consumer Information Use and Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only the healthcare provider has the knowledge and training to decide which medicines are right for a specific patient. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a limited summary of general information about the medicine's uses from the patient education leaflet and is not intended to be comprehensive. This limited summary does NOT include all information available about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not intended to provide medical advice, diagnosis or treatment and does not replace information you receive from the healthcare provider. For a more detailed summary of information about the risks and benefits of using this medicine, please speak with your healthcare provider and review the entire patient education leaflet.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.