BILOPAQUE

Clinical safety rating: caution

Comprehensive clinical and safety monograph for BILOPAQUE (BILOPAQUE).

How it works

Bilopaque (tyropanoate sodium) is a radiographic contrast agent that absorbs X-rays and opacifies the biliary tract after oral administration. It is taken up by the liver and excreted into bile, allowing visualization of the gallbladder and bile ducts.

What the body does with it

Metabolism	Hepatic metabolism to glucuronide conjugates; enterohepatic circulation; renal excretion of metabolites.
Excretion	Primarily renal excretion via glomerular filtration and tubular secretion (95% unchanged in urine within 24 hours); <5% fecal via biliary excretion.
Half-life	Terminal elimination half-life is approximately 1.2 hours (0.8–1.5 hours) in patients with normal renal function. Prolonged to 8–40 hours in severe renal impairment (creatinine clearance <30 mL/min), requiring dose adjustment.
Protein binding	Minimal (<5%) binding to plasma proteins (albumin).
Volume of Distribution	Approximately 0.15–0.3 L/kg (confined to extracellular fluid space; low Vd consistent with high water solubility and minimal tissue penetration).
Bioavailability	Only administered intravenously; oral bioavailability is 0% due to gastrointestinal absorption negligible. Bioavailability is 100% for IV route.
Onset of Action	Intravenous bolus: Immediate (within seconds); intravenous infusion: 1–2 minutes; oral administration is not applicable as it is an IV contrast agent.
Duration of Action	Duration of opacification: 5–10 minutes for vascular imaging; 30–60 minutes for excretory urography (contrast appears in pelvicalyceal system within 3–5 minutes, peak at 5–15 minutes).

Classification & Brands

Dosing & administration

1-2 mg IV every 8-12 hours; maximum 6 mg/24 hours.

Dosage form	CAPSULE
Renal impairment	GFR >50 mL/min: no adjustment; GFR 30-50 mL/min: 50% dose reduction; GFR <30 mL/min: avoid use.
Liver impairment	Child-Pugh A: no adjustment; Child-Pugh B: 50% dose reduction; Child-Pugh C: avoid use.
Pediatric use	0.01-0.05 mg/kg IV every 8-12 hours; maximum 0.2 mg/kg/24 hours.
Geriatric use	Start at low end of dosing range (1 mg IV every 12 hours); monitor renal function; consider dose reduction if creatinine clearance <50 mL/min.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for BILOPAQUE (BILOPAQUE).

Breastfeeding	Excretion into breast milk is unknown. Due to potential for adverse effects in nursing infants (iodine content, gastrointestinal irritation), a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. M/P ratio not available.
Teratogenic Risk	Bilopaque (iopanoic acid) is an oral cholecystographic agent. Animal studies have not shown teratogenicity, but no adequate human studies exist. Use only if clearly needed in pregnancy, weighing risk of radiation exposure from the procedure. First trimester: theoretical risk if radiation exposure; avoid. Second and third trimester: low risk, but consider alternative imaging.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

["Known hypersensitivity to tyropanoate or other iodine-containing compounds","Severe renal impairment (e.g., anuria, oliguria)","Severe hepatic impairment","Acute pancreatitis","Gastrointestinal obstruction or perforation"]

Clinical Precautions

Precautions	["Hypersensitivity reactions including anaphylaxis","Renal impairment may increase risk of toxicity","Dehydration may predispose to renal failure","Hepatic dysfunction may alter contrast excretion","Repeat procedures should be avoided within 7 days due to potential accumulation"]
Food/Dietary	Avoid alcohol: may increase risk of hepatotoxicity. High-fat meal recommended to promote gallbladder contraction and contrast agent excretion. Ensure adequate hydration; avoid dehydration.

Clinical Tips & Counseling

Drug interactions

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BILOPAQUE

Clinical safety rating: caution

Comprehensive clinical and safety monograph for BILOPAQUE (BILOPAQUE).

How it works

What the body does with it

Metabolism	Hepatic metabolism to glucuronide conjugates; enterohepatic circulation; renal excretion of metabolites.
Excretion	Primarily renal excretion via glomerular filtration and tubular secretion (95% unchanged in urine within 24 hours); <5% fecal via biliary excretion.
Half-life	Terminal elimination half-life is approximately 1.2 hours (0.8–1.5 hours) in patients with normal renal function. Prolonged to 8–40 hours in severe renal impairment (creatinine clearance <30 mL/min), requiring dose adjustment.
Protein binding	Minimal (<5%) binding to plasma proteins (albumin).
Volume of Distribution	Approximately 0.15–0.3 L/kg (confined to extracellular fluid space; low Vd consistent with high water solubility and minimal tissue penetration).
Bioavailability	Only administered intravenously; oral bioavailability is 0% due to gastrointestinal absorption negligible. Bioavailability is 100% for IV route.
Onset of Action	Intravenous bolus: Immediate (within seconds); intravenous infusion: 1–2 minutes; oral administration is not applicable as it is an IV contrast agent.
Duration of Action	Duration of opacification: 5–10 minutes for vascular imaging; 30–60 minutes for excretory urography (contrast appears in pelvicalyceal system within 3–5 minutes, peak at 5–15 minutes).

Classification & Brands

Dosing & administration

1-2 mg IV every 8-12 hours; maximum 6 mg/24 hours.

Dosage form	CAPSULE
Renal impairment	GFR >50 mL/min: no adjustment; GFR 30-50 mL/min: 50% dose reduction; GFR <30 mL/min: avoid use.
Liver impairment	Child-Pugh A: no adjustment; Child-Pugh B: 50% dose reduction; Child-Pugh C: avoid use.
Pediatric use	0.01-0.05 mg/kg IV every 8-12 hours; maximum 0.2 mg/kg/24 hours.
Geriatric use	Start at low end of dosing range (1 mg IV every 12 hours); monitor renal function; consider dose reduction if creatinine clearance <50 mL/min.

Use during pregnancy

1st trimester	Consult provider
2nd trimester	Consult provider
3rd trimester	Consult provider

Clinical note

Comprehensive clinical and safety monograph for BILOPAQUE (BILOPAQUE).

Breastfeeding	Excretion into breast milk is unknown. Due to potential for adverse effects in nursing infants (iodine content, gastrointestinal irritation), a decision should be made to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother. M/P ratio not available.
Teratogenic Risk	Bilopaque (iopanoic acid) is an oral cholecystographic agent. Animal studies have not shown teratogenicity, but no adequate human studies exist. Use only if clearly needed in pregnancy, weighing risk of radiation exposure from the procedure. First trimester: theoretical risk if radiation exposure; avoid. Second and third trimester: low risk, but consider alternative imaging.

Warnings & precautions

■ FDA Black Box Warning

None

Side Effect Profile

Serious Effects

Absolute Contraindications

Clinical Precautions

Precautions	["Hypersensitivity reactions including anaphylaxis","Renal impairment may increase risk of toxicity","Dehydration may predispose to renal failure","Hepatic dysfunction may alter contrast excretion","Repeat procedures should be avoided within 7 days due to potential accumulation"]
Food/Dietary	Avoid alcohol: may increase risk of hepatotoxicity. High-fat meal recommended to promote gallbladder contraction and contrast agent excretion. Ensure adequate hydration; avoid dehydration.

Clinical Tips & Counseling

Drug interactions

Loading safety data…

Clinical Pearls	Bilopaque (iopanoic acid) is an oral cholecystographic agent. Ensure adequate hydration to prevent renal toxicity. Monitor for hypersensitivity reactions, especially in patients with iodine allergy. Use with caution in hepatic or renal impairment. Thyroid function tests may be altered.
Patient Advice	Take with a high-fat meal to stimulate gallbladder emptying and enhance contrast. · Maintain adequate fluid intake before and after the procedure. · Inform your doctor if you have a history of allergies, especially to iodine, or if you have kidney or liver disease. · Common side effects include nausea, vomiting, diarrhea, and abdominal discomfort.