sulfisoxazole acetyl (redirected from Gantrisin Pediatric Suspension)

sulfisoxazole acetyl

Gantrisin Pediatric Suspension

Pharmacologic class: Sulfonamide (short-acting)

Therapeutic class: Anti-infective

Pregnancy risk category C

Action

Inhibits formation of bacterial folic acid from para-aminobenzoic acid (PABA), preventing bacterial cell-wall synthesis and exerting a bacteriostatic effect

Availability

Suspension: 500 mg/5 ml

Tablets: 500 mg

⊘Indications and dosages

➣ Urinary tract and systemic infections

Adults: Initially, 2 to 4 g P.O.; then 4 to 8 g daily in four to six equally divided doses

Children ages 2 months and older: Initially, 75 mg/kg P.O. or 2 g/m², then 150 mg/kg or 4 g/m² daily in four to six equally divided doses. Total daily dosage shouldn't exceed 6 g.

Dosage adjustment

• Renal impairment

Contraindications

• Hypersensitivity to drug, other sulfonamides, sulfonylureas, or thiazide or loop diuretics
• Pregnancy at term or when premature birth is possible
• Infant younger than 2 months (except in congenital toxoplasmosis)
• Porphyria

Precautions

Use cautiously in:
• urinary obstruction, renal or hepatic disease, bronchial asthma, G6PD deficiency, group A beta-hemolytic streptococcal infections
• history of multiple allergies
• pregnant (before term) or breastfeeding patients.

Administration

• Give with a full glass of water. Encourage good fluid intake to minimize crystal formation in urine.

Route	Onset	Peak	Duration
P.O.	Unknown	1-4 hr	Unknown

Adverse reactions

CNS: headache, depression, hallucinations, insomnia, drowsiness, vertigo, fatigue, apathy, anxiety, ataxia, polyneuritis, peripheral neuropathy, seizures

CV: allergic myocarditis or pericarditis

EENT: optic neuritis, transient myopia, periorbital edema, tinnitus

GI: nausea, vomiting, abdominal pain, pancreatitis, stomatitis, glossitis, dry mouth, anorexia, pseudomembranous colitis

GU: hematuria, proteinuria, crystalluria, toxic nephrosis with oliguria and anuria, renal failure

Hematologic: megaloblastic anemia, agranulocytosis, aplastic anemia, thrombocytopenia, leukopenia, hemolytic anemia

Hepatic: jaundice, hepatitis, hepatocellular necrosis

Respiratory: shortness of breath, pleuritis, allergic pneumonitis, pulmonary infiltrates, fibrosing alveolitis

Skin: local irritation, urticaria, pruritus, generalized skin eruption, alopecia, exfoliative dermatitis, photosensitivity reaction, epidermal necrolysis, erythema multiforme, Stevens-Johnson syndrome

Other: chills, drug fever, hypersensitivity reactions including anaphylaxis, serum sickness, lupus-like syndrome

Interactions

Drug-drug. Cyclosporine: increased nephrotoxicity

Hydantoins: increased hydantoin blood level

Indomethacin, probenecid: increased sulfisoxazole blood level

Methenamine: increased risk of crystalluria, causing serious adverse reactions

Methotrexate: increased risk of bone marrow depression

Oral anticoagulants: increased anticoagulant effect

PABA, PABA-derived local anesthetics: inhibited sulfisoxazole action

Sulfonylureas: increased risk of hypoglycemia

Thiazide diuretics: increased thrombocytopenic effect

Thiopental, uricosuric drugs: increased effects of these drugs

Drug-diagnostic tests. Bilirubin, blood urea nitrogen, creatinine, eosinophils, transaminases: increased levels

Granulocytes, hemoglobin, platelets, white blood cells: decreased levels

Urine glucose test: false-positive result

Drug-herbs. Dong quai, St. John's wort: increased risk of photosensitivity

Drug-behaviors. Sun exposure: increased risk of photosensitivity

Patient monitoring

☞ Monitor CBC with white cell differential. Watch for evidence of blood dyscrasias.
☞ Stay alert for signs of erythema multiforme. Report early signs before condition can progress to Stevens-Johnson syndrome.
• Monitor patient for signs and symptoms of superinfection, including fever, tachycardia, and chills.
☞ Monitor liver function tests. Be alert for signs and symptoms of hepatitis.
☞ Check kidney function test results weekly. Evaluate patient's fluid intake, urine output, and urine pH. Report hematuria, oliguria, or anuria right away.
• Monitor neurologic status. Report seizures, hallucinations, or depression.

Patient teaching

• Tell patient to take on regular schedule as prescribed, along with a full glass of water. Advise him to drink plenty of fluids to minimize crystal formation in urine.
• Instruct patient to complete full course of treatment, even if he feels better after a few days.
☞ Tell patient to watch for and immediately report signs and symptoms of hypersensitivity reaction, especially rash.
☞ Advise patient that drug can cause blood disorders, GI and liver problems, serious skin reactions, and other infections. Describe key warning signs and symptoms (easy bruising or bleeding, severe diarrhea, unusual tiredness, yellowing of skin or eyes, sore throat, rash, cough, mouth sores, fever). Tell him to report these right away.
☞ Encourage patient to promptly report scant urine, bloody urine, or inability to urinate.
• Instruct patient to contact prescriber if he develops depression.
• Teach patient effective ways to counteract photosensitivity effect. Tell him that dong quai and St. John's wort increase phototoxicity risk and should be avoided during therapy.
• Advise female patient to inform prescriber if she is pregnant. Caution her not to take drug near term or when breastfeeding.
• As appropriate, review all other significant and life-threatening adverse reactions and interactions, especially those related to the drugs, tests, herbs, and behaviors mentioned above.