Usage
Meglumine diatrizoate is a radiopaque contrast agent used to visualize the gastrointestinal tract and urinary system during radiographic procedures. It can also be used for contrast enhancement in computed tomography of the torso and for retrograde cystourethrography. Its pharmacological classification is as an iodinated contrast medium. The mechanism of action involves the high atomic weight of iodine attenuating X-rays, resulting in enhanced visualization of the organ or system being studied.
Alternate Names
Meglumine amidotrizoate, Diatrizoic acid meglumine salt. Brand names include Gastrografin, Hypaque, Cystografin, MD-Gastroview, Renografin-60.
How It Works
Pharmacodynamics: Meglumine diatrizoate enhances the radiographic contrast of the gastrointestinal tract and urinary system through X-ray attenuation by its iodine molecules. It has a mild laxative effect due to high osmolarity. Systemically absorbed contrast may also incidentally opacify the urinary tract.
Pharmacokinetics: Orally or rectally administered meglumine diatrizoate is minimally absorbed from the intact gastrointestinal tract. Intravenous administration allows for systemic distribution. It is excreted primarily through the kidneys. The rate of elimination can be reduced in patients with renal impairment. Metabolism is limited.
Dosage
Standard Dosage
Adults:
- Oral: 30–90 mL, depending on the examination.
- Rectal: 240 mL diluted in 1000 mL of tap water.
- Intravenous (IV): Varies based on the procedure; for example, excretory urography: 25-50 mL.
Children:
Dosages are adjusted based on age and weight. Dilution is crucial, especially for infants and young children:
- Infants (<10 kg): Dilution of 1 part Gastrografin to 3 parts water recommended
- Children (5-10 years): Oral: 60 mL, Rectal: 90 mL diluted in 500 mL tap water
- Children (< 5 years): Oral: 30 mL, Rectal: Dilute 1:5
Special Cases:
- Elderly Patients and those with debility: Use 1:1 dilution for Oral/Rectal Administration.
- Patients with Renal Impairment: Use with caution and monitor closely as excretion is impaired. Dosage reduction may be necessary.
- Patients with Hepatic Dysfunction: Limited data available. Use with caution.
- Patients with Comorbid Conditions: In patients with diabetes, especially those with diabetic nephropathy, and those with dehydration, careful evaluation of renal function and fluid balance is necessary.
Clinical Use Cases
Dosing is highly variable and depends on specific requirements and procedural details:
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Intubation: Not typically applicable for meglumine diatrizoate administration.
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Surgical Procedures: Dosage varies widely according to the imaging requirements of the procedure.
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Mechanical Ventilation: Not usually applicable for this contrast agent.
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Intensive Care Unit (ICU) Use: Dosage individualized based on patient factors and procedures.
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Emergency Situations: Not usually the contrast agent of choice.
Dosage Adjustments
Adjustments based on renal and hepatic function, age, and hydration status are essential.
Side Effects
Common Side Effects:
Nausea, vomiting, diarrhea, rash.
Rare but Serious Side Effects:
Allergic reactions (including anaphylaxis), renal failure (especially in high-risk individuals), pulmonary edema, thyroid dysfunction, hypovolemia, hypotension, shock-like state.
Long-Term Effects:
Hypothyroidism can occur, especially in infants following exposure to high iodine levels.
Adverse Drug Reactions (ADR):
Anaphylaxis and severe allergic reactions can occur.
Contraindications
Hypersensitivity to diatrizoate salts or any components. Not for intrathecal use. Severe dehydration.
Drug Interactions
Metformin, beta-blockers, and interleukins can interact with meglumine diatrizoate. Certain laboratory tests can be affected (e.g. Thyroid function tests).
Pregnancy and Breastfeeding
Pregnancy Category B. Small amounts excreted in breast milk, discontinue breast feeding for 24hrs post-administration.
Drug Profile Summary
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Mechanism of Action: Enhances radiographic contrast by attenuating X-rays due to iodine content.
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Side Effects: Nausea, vomiting, diarrhea, rash, allergic reactions, renal failure, pulmonary edema, thyroid dysfunction.
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Contraindications: Hypersensitivity, intrathecal use, severe dehydration.
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Drug Interactions: Metformin, beta-blockers, interleukins.
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Pregnancy & Breastfeeding: Category B, small amounts in breast milk, interrupt breastfeeding for 24 hours.
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Dosage: Varies depending on route and indication.
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Monitoring Parameters: Renal function, hydration status, electrolytes, thyroid function.
Popular Combinations
Used in conjunction with other contrast agents for CT of the torso (IV contrast).
Precautions
Evaluate renal function and hydration status. Avoid rapid or excessive administration. Pre-screen for iodine allergy. Carefully consider risks in infants, young children, and debilitated patients.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Meglumine Diatrizoate?
A: Dosage varies greatly depending on the route of administration (oral, rectal, IV) and the specific diagnostic procedure being performed. Please consult the detailed dosage guidelines section.
Q2: What are the primary contraindications for its use?
A: Known hypersensitivity to diatrizoate or any component of the formulation, intrathecal administration, and severe dehydration.
Q3: How should Meglumine Diatrizoate be administered?
A: Orally, rectally, or intravenously, depending on the specific procedure.
Q4: Can Meglumine Diatrizoate be used in patients with renal impairment?
A: Use with extreme caution and with appropriate dose adjustments. Monitor renal function closely.
Q5: What are the common side effects?
A: Nausea, vomiting, diarrhea, and skin reactions (rash, hives).
Q6: Are there any potential drug interactions?
A: Yes, clinically significant interactions exist with metformin, beta-blockers, and interleukins.
Q7: Can this contrast agent be used in pregnant or breastfeeding women?
A: Pregnancy Category B. Use only if clearly needed. Discontinue breastfeeding for 24 hours following administration.
Q8: What is the mechanism of action for Meglumine Diatrizoate?
A: It works by attenuating X-rays due to the iodine content, increasing the contrast of the imaged area.
Q9: What precautions should be taken when administering Meglumine Diatrizoate to pediatric patients?
A: Careful dilution is essential, especially for infants and young children. Ensure adequate hydration.
Q10: Are there any specific monitoring parameters?
A: Monitor renal function, electrolytes, thyroid function, and hydration status, especially in high-risk individuals.
