Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (703 page)

   “Hyperchloremia” in bromide intoxication (if chloride determination by colorimetric method).

   False increase in serum chloride or HCO
₃
⁻
.

   False decrease in serum sodium (e.g., hyperlipidemia, hyperviscosity)

   Increased unmeasured cations

   Hyperkalemia, hypercalcemia, hypermagnesemia

   Increased proteins in multiple myeloma, paraproteinemias, polyclonal gammopathies (these abnormal proteins are positively charged and lower the AG).

   Lithium and bromide overdose.

   Simultaneous changes in ions may cancel each other out, leaving AG unchanged (e.g., increased Cl
⁻
and decreased HCO
₃
⁻
). The change in AG should equal change in HCO
₃
⁻
; otherwise a mixed, rather than simple, acid– base disturbance is present.

ANTIARRHYTHMIC DRUGS

See Cardiovascular Drugs.

ANTIBIOTICS

   Definition

   Antibiotics are substances that destroy or inhibit the growth of microorganisms. Antibiotics consist of chemical groups such as β-lactams, polyenes, macrolides, tetracyclines, aminoglycosides, and sulfonamides. Names include amikacin, chloramphenicol, gentamicin, kanamycin, streptomycin, tobramycin, and vancomycin.

   
Normal therapeutic (and toxic) levels:
see Table 16.5.

TABLE 16–5. Therapeutic and Toxic Serum Concentrations for Antibiotics

   Use