|Drugs search, click the first letter of a drug name: | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | 1 | 2 | 3 | 4 | 5 | 6 | 8 | 9
Generic Name: diatrizoate meglumine and diatrizoate sodium
Dosage Form: Solution
Gastrografin (Diatrizoate Meglumine and Diatrizoate Sodium Solution) is a palatable lemon-flavored water-soluble iodinated radiopaque contrast medium for oral or rectal administration only. Each mL contains 660 mg diatrizoate meglumine and 100 mg diatrizoate sodium; pH has been adjusted to 6.0 to 7.6 with sodium hydroxide. Each mL contains approximately 4.8 mg (0.21 mEq) sodium and 367 mg organically bound iodine. Inactive ingredients: edetate disodium, flavor, polysorbate 80, purified water, saccharin sodium, simethicone, and sodium citrate.
Diatrizoate meglumine is designated chemically as 1-deoxy-1-(methylamino)-D-glucitol 3,5-diacetamido-2,4,6-triiodo-benzoate (salt); diatrizoate sodium is monosodium 3, 5-diacetamido-2,4,6-triiodobenzoate. Structural formulas:
Gastrografin - Clinical Pharmacology
The most important characteristic of contrast media is the iodine content. The relatively high atomic weight of iodine contributes sufficient radiodensity for radiographic contrast with surrounding tissues.
Diagnostic enteral radiopaque agents have few known pharmacological effects. Diatrizoate meglumine and diatrizoate sodium exert a mild laxative effect attributable to their high osmolarity.
Diatrizoate meglumine and diatrizoate sodium are sparingly absorbed from the intact gastrointestinal tract, and therefore permit gastrointestinal opacification and delineation after oral or rectal administration. Oral administration is used for radiographic evaluation of the esophagus, stomach and proximal small intestine. Rectal administration is used for examination of the colon; however, visualization of the distal small bowel is generally unsatisfactory, since the hypertonicity of the medium causes intraluminal diffusion of water with subsequent dilution of the medium. Enough absorption from the gastrointestinal tract to permit incidental visualization of the urinary tract has been reported; this should also be considered when thyroid testing is being contemplated, since iodine-mediated thyrotropic effects may occur (see PRECAUTIONS).
Indications and Usage for Gastrografin
Gastrografin (Diatrizoate Meglumine and Diatrizoate Sodium Solution) is indicated for radiographic examination of segments of the gastrointestinal tract (esophagus, stomach, proximal small intestine, and colon). The preparation is particularly indicated when a more viscous agent such as barium sulfate, which is not water-soluble, is not feasible or is potentially dangerous.
Gastrografin may also be used as an adjunct to contrast enhancement in computed tomography of the torso (body imaging); the preparation is indicated, in conjunction with intravenous administration of a radiopaque contrast agent, when unenhanced imaging may not provide sufficient definition in distinguishing normal loops of bowel from adjacent organs or areas of suspected pathology.
There are no absolute contraindications to the use of Gastrografin (Diatrizoate Meglumine and Diatrizoate Sodium Solution) as recommended (see PRECAUTIONS, General).
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. See DOSAGE AND ADMINISTRATION for recommended dilutions that must be used for infants and young children (under 10 kg) and for dehydrated or debilitated patients. Electrolyte disturbances must be corrected prior to using hypertonic solutions. 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.
The possibility of accidental aspiration into the trachea or into a tracheoesophageal fistula following ingestion or instillation, could result in serious pulmonary complications (e.g., pulmonary edema or pneumonitis) even though the medium may be promptly expectorated. Bronchial entry of any orally administered contrast medium causes a copious osmotic effusion. Therefore, pulmonary entry by aspiration and use in patients with esophagotracheal fistula should be avoided.
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.
The possibility of a reaction should always be considered. Patients at increased risk include those with a history of a previous reaction to a contrast medium, patients with a known sensitivity to iodine per se, and patients with a known clinical hypersensitivity (bronchial asthma, hay fever, and food allergies). A positive history of allergies or hypersensitivity does not arbitrarily contraindicate the use of a contrast agent when a diagnostic procedure is thought essential, but caution should be exercised (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 increases 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:
Drug/Laboratory Test InteractionsThyroid 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.Pancreatic Tests
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.
|Gastrografin (diatrizoate meglumine and diatrizoate sodium)|
|© Copyright by Drugspedia.net 2006-2007. All rights reserved|