Barium sulfate suspension

V Gallardo, L Zurita, A Ontiveros, JDG Duran. Interfacial properties of barium sulfate suspensions. Implications in their stability. J Pharm Sci 89 1134— 1142, 2000. 

Consider barium sulfate, a sparingly soluble salt. X-ray technicians give patients a barium sulfate suspension to drink before taking an X-ray of the large intestine. A suspension of barium sulfate is opaque to X-rays, which helps to define this part of the body. (See Figure 9.4.)... 

Recent investigations [18] to quantify stabilization were successful in correlating to observed stability of colloidal barium sulfate suspensions with the suspension composition and in particular the concentrations of Ba2+- and... 

Sacchetti G. 1972. Gastric emptying of barium sulfate suspensions in humans A useful tool for clinical investigations. Farmaco Prat 27 80-88. 

Shaffer HA, Eckard DA, De Lange EE, et al. 1988. Allergy to barium sulfate suspension with angioedema of the stomach and small bowel. Gastrointest Radiol 13 221-223. 

U. 8. 2,746,906 Stabilizer for barium sulfate suspension (carboxymethyl-) Midland Chemical Corporation, Dayton... 

Barium sulfate preparations arc used to study the esophagus, stomach, and duodenum as part of an csophagram nr UGI series and are given orully. Most patients tlnd the taste of these dense mixtures ueeeptuble (they are usually given a strawberry or lemon flavor), but they dislike the heavy texture of the barium. Barium sulfate suspensions are also given orally to study the entire small bowel (SBFT) or rec-tally to examine the colon (BE) (Fig. 1.3-18). 

The viscosity of barium sulfate suspension is determined by the quantity and size of particles and can be modified by added peptizing agents (52). A thick paste of barium sulfate in water can be peptized or thinned by the addition of sodium citrate and sorbitol. The function of the citrate is to stabilize the colloidal... 

Many different preparations of colloidal barium sulfate for roentgenography are available commercially. The so-called barium meals are not limited to liquid suspensions they also appear as tablets (73). Barium sulfate suspensions containing an effervescent agent have been introduced for use in doublecontrast studies (74,75). Barium sulfate may also be coated with Fe203, MgO, and Al Oa (63,761. The coated material has good dispersibility and very low viscosity in acidic media. Other barium preparations are also useful. A barium titanate suspension was compared with barium sulfate (72). An emulsified mixture containing castor oil and barium sulfate can visualize colon fistula more economically than can iodinated contrast media (77). 

Two kinds of contrast media are available for oral and rectal administration iodinated, aqueous solutions and barium sulfate suspensions. Both substances are used alike, and no serious side effects have so far been reported when properly dosed. Nevertheless, iodinated solutions have some pharmacological and physical properties that make them superior to barium sulfate suspensions ... 

In some patients, the use of barium sulfate causes circular thickening of the bowel wall - mainly in distal small bowel segments - which closely resembles the appearance of enteritis and can be misinterpreted. This effect may be attributable to edematous swelling of the mucosa due to the hydrophilic nature of the barium sulfate suspension. 

The definition of the technique relies on the stability of the barium sulfate suspension under the variety of conditions of acidity and secretion rate that are seen in patients. >etailed examination depends on a tightly packed film of suspension adhering to the various crevices of the mucosal wall. Packing is maximal when a wide range of particle sizes of barium sulfate is present. 

The authors (15) have found that the following methods are reliable and convenient when a rapid method for a large number of samples is required. The barium sulfate suspension is not stabilized with gelatin and absorption readings should be taken within ten minutes. 

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