GIAZO
Clinical safety rating: caution
Comprehensive clinical and safety monograph for GIAZO (GIAZO).
Balsalazide is a prodrug that is converted by colonic bacteria into mesalamine (5-aminosalicylic acid), which inhibits prostaglandin and leukotriene production, reducing colonic inflammation.
| Metabolism | Primarily metabolized by colonic bacteria via azoreduction to mesalamine and 4-aminobenzoyl-beta-alanine. Mesalamine undergoes hepatic metabolism via N-acetylation to N-acetyl-5-aminosalicylic acid. |
| Excretion | Primarily metabolized in the gut mucosa and liver to N-acetyl-5-aminosalicylic acid. Renal excretion of acetylated metabolite accounts for ~25-30% of dose; fecal excretion of parent drug and metabolite ~50-60%. Biliary excretion minimal. |
| Half-life | Terminal elimination half-life approximately 0.5-1.0 hour for 5-ASA (active); metabolite half-life ~5-10 hours. Clinical context: short half-life necessitates multi-matrix release formulation for once-daily dosing in ulcerative colitis. |
| Protein binding | 5-ASA is ~40-50% bound to plasma proteins (mainly albumin); N-acetyl-5-ASA ~80-90% bound. |
| Volume of Distribution | Apparent Vd ~0.4 L/kg (based on total 5-ASA), indicating distribution primarily into extracellular fluid. |
| Bioavailability | Oral (tablet): 5-ASA bioavailability ~20-30% due to extensive presystemic metabolism; the multi-matrix system targets colonic release, reducing systemic exposure. No IV formulation. |
| Onset of Action | Oral (once-daily): clinical improvement may be observed within 2-4 weeks; full therapeutic effect typically by 8 weeks. |
| Duration of Action | After absorption, systemic 5-ASA cleared rapidly; topical (colonic) action persists as long as formulation releases drug, designed for ~24-hour coverage with once-daily dosing. |
| Molecular Weight | 398.46 |
Adults: 2 tablets (1.2 g) orally three times daily (3.6 g/day) for up to 6 weeks.
| Dosage form | TABLET |
| Renal impairment | Contraindicated in severe renal impairment (eGFR <30 mL/min/1.73 m2); no dose adjustment recommended for mild to moderate impairment. |
| Liver impairment | No specific guidelines; use caution in severe hepatic impairment (Child-Pugh C). |
| Pediatric use | Not approved for use in pediatric patients under 18 years of age. |
| Geriatric use | No specific dose adjustment; monitor renal function and consider increased sensitivity due to age-related decline. |
| 1st trimester | Limited human data; animal studies show risk. Use only if benefit outweighs risk. Avoid in first trimester if possible. |
| 2nd trimester | May be used if benefit outweighs risk. Monitor for fetal growth and amniotic fluid volume. |
| 3rd trimester | Avoid near term due to risk of premature closure of ductus arteriosus and oligohydramnios. |
Clinical note
Comprehensive clinical and safety monograph for GIAZO (GIAZO).
| Placental transfer | Crosses placenta; detectable in fetal plasma and amniotic fluid. |
| Breastfeeding | Excreted into human milk in low amounts. Use caution; monitor infant for diarrhea, rash, and hepatic effects. |
| Lactation Rating |
■ FDA Black Box Warning
No FDA black box warning.
| Serious Effects |
Hypersensitivity to 5-ASA, salicylates, or any componentSevere renal impairment (eGFR <30 mL/min/1.73 m²)Severe hepatic impairment
| Precautions | Renal impairment (risk of nephrotoxicity, including interstitial nephritis), Pyloric stenosis or gastrointestinal obstruction (delayed transit may cause drug accumulation), Mesalamine-induced acute intolerance syndrome (cramping, abdominal pain, bloody diarrhea, fever, headache, rash), Photosensitivity in patients with preexisting skin conditions (e.g., atopic dermatitis, eczema) |
| Food/Dietary | No specific food interactions. Avoid alcohol due to gastrointestinal irritation. Maintain adequate fluid intake. No restriction on dairy or other foods. |
Loading safety data…
| L3 (Moderately Safe) |
| Teratogenic Risk | GIAZO (balsalazide disodium) is a prodrug of mesalamine. Mesalamine and its metabolites cross the placenta. FDA Pregnancy Category B. No evidence of teratogenicity in human studies, but limited data in first trimester. In second and third trimesters, risk of maternal anemia and possible fetal renal impairment. Use only if clearly needed. |
| Fetal Monitoring | Monitor maternal CBC, renal function (serum creatinine, BUN), and pregnancy progression. In third trimester: assess fetal growth and amniotic fluid volume. Watch for maternal oligohydramnios and fetal renal dysfunction. |
| Fertility Effects | No known adverse effects on fertility. Balsalazide and mesalamine do not appear to impair male or female fertility. |
| Clinical Pearls | GIAZO (balsalazide disodium) is a prodrug of mesalamine activated by colonic bacteria. It is indicated for mild to moderately active ulcerative colitis. Dose is 3 capsules (2.25 g) three times daily for 8 weeks. Switch to mesalamine if compliance is an issue due to high pill burden. Monitor renal function and CBC periodically. Avoid in patients with salicylate allergy. May cause yellow-orange discoloration of urine and soft contact lenses. |
| Patient Advice | Take GIAZO exactly as prescribed, usually 3 capsules three times a day for 8 weeks. · Swallow capsules whole; do not crush or chew. · Drink plenty of fluids to prevent dehydration from diarrhea. · Urine may turn yellow-orange; this is harmless. · Avoid contact lenses if they become discolored. · Report new or worsening symptoms such as abdominal pain, fever, or bloody diarrhea. · Tell your doctor if you have kidney disease, bleeding problems, or are pregnant/breastfeeding. · Avoid aspirin or NSAIDs unless directed by your doctor. · Do not stop taking without consulting your doctor. |