Dehydration: Administration of hypertonic Gastrografin solutions may lead to hypovolemia and hypotension due to fluid loss from the intestine. A 1 in 4.6 (1:4.6) dilution of Gastrografin yields an approximately isotonic 16.5 percent diatrizoate salts solution; less dilute solutions are hypertonic and may lead to intraluminal movement of fluid with resulting hypovolemia. In young or debilitated children and in elderly cachectic persons, the loss of plasma fluid may be sufficient to cause a shock-like state. If Gastrografin is used in infants and children (under 10 kg) or in dehydrated or debilitated patients, the solution must be prepared using the specific dilutions described in DOSAGE AND ADMINISTRATION. In debilitated patients and in patients with electrolyte imbalances, postprocedural monitoring of hydration, serum osmolarity, electrolytes and clinical status is essential. In pediatric or severely debilitated patients, the maintenance of an open intravenous fluid line for rehydration may be advisable should hypotension or shock supervene. Electrolyte disturbances must be corrected prior to the administration of any hypertonic Gastrografin solutions.
Aspiration: Aspiration of Gastrografin into the trachea and airways may result in serious pulmonary complications including, pulmonary edema, pneumonitis or death Bronchial entry of any orally administered contrast medium causes a copious osmotic effusion. Therefore, avoid use of Gastrografin in patients with esophagotracheal fistula and minimize risks for pulmonary aspiration in all patients. If Gastrografin is given by nasogastric tube, the position of the tube in the stomach must be verified before administration.
Anaphylactic reactions: Anaphylactic reactions, including fatalities, have been reported with the use of Gastrografin. Patients at increased risk include those with a history of a previous reaction to a contrast medium, patients with a known sensitivity to iodine, and patients with a known clinical hypersensitivity (bronchial asthma, hay fever, and food allergies). Medical personnel trained in the treatment of anaphylactic reactions and the necessary drugs and medical equipment should always be readily available when Gastrografin is used.
Diagnostic procedures which involve the use of radiopaque contrast agents should be carried out under the direction of personnel with the prerequisite training and with a thorough knowledge of the particular procedure to be performed. Appropriate facilities should be available for coping with any complication of administration, as well as for treatment of reaction to the contrast medium (see ADVERSE REACTIONS, and PRECAUTIONS, Information for the Patient).
Rectal administration of undiluted Gastrografin (Diatrizoate Meglumine and Diatrizoate Sodium Solution) in any patient, particularly with large doses and/or in those with overdistention, has been reported to be associated with mucosal irritation.
Cases of hyperthyroidism have been reported with the use of oral contrast media. Some of these patients reportedly had multinodular goiters which may have been responsible for the increased hormone synthesis in response to excess iodine. Administration of an intravascular iodinated radiopaque diagnostic agent to a hyperthyroid patient precipitated thyroid storm; a similar situation could follow administration of oral preparations of iodides. Therefore, caution should be exercised when administering enteral gastrointestinal radiopaque agents to hyperthyroid and euthyroid goiterous patients.
Consideration should be given to the potential for precipitation of water-soluble contrast agents under conditions that may promote hyperacidity (i.e., fasting, emotional upset, or stress). Harmful effects directly attributable to precipitate formation have not been reported. However, the possibility of interpreting the precipitate radiologically as an anatomical abnormality (i.e., ulceration of the stomach or small intestine) or injury, should be kept in mind.
Information for the Patient
Patients should receive the following information and instructions:
- This drug has been prescribed to perform an x-ray of the gastrointestinal tract.
- Inform the physician if pregnant or if allergic to iodine, any foods, or x-ray materials.
- The iodine in diatrizoate salts may interfere with some thyroid tests if these are needed in the future. Inform the attending physician at that time about this gastrointestinal study.
- This drug may cause abdominal cramping, nausea, vomiting, diarrhea, skin rashes, itching, heartburn, dizziness, or headache in some patients, but most reactions are mild and pass quickly.
Drug/Laboratory Test Interactions
Thyroid Function Tests
The results of protein bound iodine (PBI) and radioactive iodine uptake studies, which depend on iodine estimations, will not accurately reflect thyroid function for six months, and possibly as long as one year, following the administration of diagnostic enteral radiopaque media.
Thyroid function tests, if indicated, generally should be performed prior to the administration of any iodinated agent. However, thyroid function can be evaluated after use of these agents by using T3 resin uptake and total or free thyroxine (T4) assays which are not dependent on iodine estimations.
Small quantities of contrast medium in the intestinal tract may cause false low trypsin values when determined spectrophotometrically. Therefore, duodenal instillation should not precede pancreatic function tests involving spectrophotometric trypsin assays.
Any test which might be affected by contrast media should be performed prior to administration of the contrast medium.
Impairment of Fertility
Long-term studies in animals have not been performed to evaluate carcinogenic or mutagenic potential, or possible impairment of fertility in males or females.
Pregnancy Category B
When administered intravenously, diatrizoate salts cross the placenta and are evenly distributed in fetal tissues.
No teratogenic effects attributable to diatrizoate meglumine or diatrizoate sodium have been observed in teratology studies performed in animals. There are, however, no adequate and well-controlled studies in pregnant women. Because small amounts of these agents may be absorbed, and animal teratology studies are not always predictive of human response, these agents should be used during pregnancy only when clearly needed.
Procedures including radiation involve a certain risk related to the exposure of the fetus.
Diatrizoate meglumine is excreted in breast milk following intravascular administration.
Because small amounts of enteral gastrointestinal radiopaque agents may be absorbed following oral or rectal administration, caution should be exercised when they are administered to a nursing woman.
See WARNINGS, and PRECAUTIONS, General.
Local injury to the colonic mucosa, particularly in the presence of underlying disease which interferes with intestinal viability, has been reported in cases where recommended doses and dilutions (see DOSAGE AND ADMINISTRATION) were not used; when extemporaneous dosage is elected, the polysorbate 80 level in the dose may be a contributing factor to injury.