SIDE EFFECTS
Adverse reactions, such
as nausea, vomiting, diarrhea and abdominal
cramping, accompanying the use of barium
sulfate formulations are infrequent and usually
mild. Severe reactions (approximately 1 in
1,000,000) and fatalities (approximately
1 in 10,000,000) have occurred. Procedural
complications are rare, but may include
aspiration pneumonitis, granuloma formation,
intravasation, embolization and peritonitis
following intestinal perforation, vasovagal and
syncopal episodes, and fatalities.
Allergic Reactions
Due to the increased
likelihood of allergic reactions in atopic patients,
it is important that a complete history of known
and suspected allergies as well as allergic-like
symptoms, e.g., rhinitis, bronchial asthma,
eczema and urticaria, be obtained prior to any
medical procedure utilizing these products. A
mild allergic reaction would most likely include
generalized pruritus, erythema or urticaria
(approximately 1 in 250,000). Such reactions
will generally respond to an antihistamine
such as 50 mg of diphenhydramine or its
equivalent. In the rarer, more serious reactions
(approximately 1 in 1,000,000) laryngeal edema,
bronchospasm or hypotension could develop.
Severe reactions which may require emergency
measures are often characterized by peripheral
vasodilation, hypotension, reflex tachycardia,
dyspnea, agitation, confusion and cyanosis,
progressing to unconsciousness. Treatment
should be initiated immediately with 0.3 to
0.5 cc of 1:1000 epinephrine subcutaneously.
If bronchospasm predominates, 0.25 to
0.50 grams of intravenous aminophylline should
be given slowly. Appropriate vasopressors might
be required. Adrenocorticosteroids, even if
given intravenously, exert no significant effect
on the acute allergic reactions for a few hours.
The administration of these agents should not
be regarded as emergency measures for the
treatment of allergic reactions. Apprehensive
patients may develop weakness, pallor, tinnitus,
diaphoresis and bradycardia following the
administration of any diagnostic agent. Such
reactions are usually non-allergic in nature and
are best treated by having the patient lie flat for an
additional 10 to 30 minutes under observation.
DRUG INTERACTIONS
The presence of barium
sulfate formulations in the GI tract may alter
the absorption of therapeutic agents taken
concomitantly. In order to minimize any potential
change in absorption, the separate administration
of barium sulfate from that of other agents should
be considered.