Last Review: November 2004
Please select the first letter of the drug of interest |
Endotoxins are a subset of pyrogens that come from gram negative bacteria.
Endotoxins are potent, toxic, very stable and present in many pharmaceutical ingredients and on surfaces that come into contact with the product when formulated for parenteral administration. They are water soluble, will pass through 0.2 µm filters, are not destroyed by autoclaving and are insoluble in organic solvents. Endotoxins are very difficult to eliminate in a final preparation; thus, procedures are generally directed at eliminating endotoxins during the preparation process.
Upon inadvertent administration of endotoxins to humans, a number of events may occur, ranging from fever through a cascade of pathogenic responses and even death.
There is an acceptable endotoxin load that the body can generally tolerate without experiencing the associated adverse events. This generally accepted endotoxin limit (EL) is defined as:
EL = K/M, where K is the threshold human pyrogenic dose of endotoxin per kg of body weight per hour, which is 5.0 EU/kg for parenteral drugs (except those administered intrathecally) and 0.2 EU/kg for the intrathecal route of administration, and where M is the maximum recommended human dose/kg of body weight that would be administered in a single one hour period.
In order to use the EL = K/M formula, the pharmacist must know the maximum endotoxin levels that are established for the drugs of interest.
Choose the drug of interest in the above menu and check the maximum allowed bacterial endotoxin unit levels in sterile preparations.
Reference:
1. US Pharmacopeial Convention, Inc. United States Pharmacopeia 27-National Formulary 22. Rockville, MD: US Pharmacopeial Convention, Inc.; 2004.
Notes:
Note 1: Refer to the current edition of the USP-NF prior to calculating and
determining endotoxin levels for the methods used.
Note 2: Where “Unit” is used, refer to the USP-NF for the description of
which Unit is indicated.
Note 3: One USP-EU is equal to one IU of endotoxin.
g = gram
IU = international unit
mEq = milliequivalent
mg = milligram
mL = milliliter
µg = microgram
USP-EU = United States Pharmacopeia-Europeum
USP-NF = United States Pharmacopeia 27-National Formulary 22