27
SI Units International System of Units Drug
Therapeutic Range Toxic Level
amikacin amitriptyline
carbamazepine clonazepam
desipramine diazepam
digoxin disopyramide
ethosuximide flecainide
gentamicin imipramine
lignocaine lithium
nortriptyline phenobarbitone
phenytoin primidone
procainamide quinidine
salicylic acid theophylline
tobramycin valproic acid
vancomycin
LABS A-F
peak: 34–51 molL trough: 7–14 molL
433–903 nmolL 21–51 molL
40–200 nmolL 281–1125 nmolL
0.35–3.5 nmolL 1–2.6 nmolL
9–18 molL 280–708 molL
0.5–2.4 molL peak:12–21 molL
trough:4 molL 610–1670 nmolL
6–21 molL 0.5–1.5 mmolL
190–570 nmolL 86–172 molL
40–80 molL 23–55 molL
17–42 molL 6–15 molL
1–2 mmolL 28–111 molL
peak: 13–21 molL trough: 4 molL
350–700 molL peak: 14–28 molL
trough: 3–7 molL
peak: 60 molL 805 nmolL
51 molL 260 nmolL
1500 nmolL 17.5 nmolL
2.6 nmolL 21 molL
1062 molL 2.4 molL
peak: 21 molL 1785 nmolL
39 molL 2 mmolL
1900 nmolL 172 molL
158 molL 55 molL
51 molL 29 molL
3.6 mmolL 111 molL
peak: 21 molL 1386 molL
peak: 28 molL
Copyright © 2005 F. A. Davis.
28
A-F
. Red-top tube. ■
Drug levels are obtained both to enhance therapeutic efficacy and to assess for toxicityoverdosepoisoning.
■
Therapeutic drug monitoring TDM is the measurement of
serum drug levels so that dosages may be adjusted to achieve optimum clinical benefit.
■ Therapeutic drug monitoring is used with
◆
cardiac glycosides e.g., digoxin
◆
antiarrhythmics e.g., lidocaine, procainamide
◆
anticonvulsants e.g., phenytoin, carbamazepine
◆
lithium
◆
theophylline
◆
aminoglycoside antibiotics gentamicin, tobramycin
◆
salicylates ■
For TDM, blood samples must be obtained at the appropriate time and after sufficient number of doses have
been administered for valid interpretation of results. ■
Peak and trough levels are drawn with some drugs, especially antibiotics. Peak levels are drawn at the point of
maximum drug absorption; trough levels are drawn just before the next dose.
Electrolytes, Serum See individual tests for normal values.
. Red-top tube. ■
Electrolytes are minerals present in body tissues and blood as dissolved salts.
■ They are electrically charged particles that help maintain
fluid and acid-base balance. They help move nutrients into cells and waste products out.
■ An electrolyte panel measures sodium Na
⫹
, potassium K
⫹
, chloride Cl
-
, and bicarbonate HCO3
-
, which is measured indirectly as CO
2
. ■
See individual tests and Anion Gap for more information.
Copyright © 2005 F. A. Davis.