Packaging and storage
Preserve in well-filled, tight, light-resistant containers, preferably of Type I or Type II glass, holding not more than 30 mL, at a temperature not exceeding 25
. Paraldehyde may be shipped in bulk containers holding a minimum of 22.5 kg (50 lb) to commercial drug repackagers only.
Labeling
The label of all containers of Paraldehyde, including those dispensed by the pharmacist, includes a statement directing the user to discard the unused contents of any container that has been opened for more than 24 hours.
NOTEThe label of bulk containers of Paraldehyde directs the commercial drug repackager to demonstrate compliance with the USP purity tests for Paraldehyde immediately prior to repackaging, and not to repackage from a container that has been opened longer than 24 hours.
Identification
Heat it with a small quantity of 2 N sulfuric acid: acetaldehyde, recognizable by its pungent odor, is produced.
Acidity
To a solution of 6.0 mL in 100 mL of water add 5 drops of phenolphthalein TS, and titrate with 1.0 N sodium hydroxide: not more than 0.50 mL is required to produce a pink color (0.5% as acetic acid).
Chloride
To 5 mL of a solution (1 in 10) add 1 drop of nitric acid and 3 drops of
silver nitrate TS: no opalescence is produced immediately.
Sulfate
To 5 mL of a solution (1 in 10) add 1 drop of hydrochloric acid and 3 drops of
barium chloride TS: no turbidity is produced.
Limit of nonvolatile residue
Heat 5.0 mL in a small, tared evaporating dish on a steam bath: no disagreeable odor is noticeable as the last portions evaporate, and, when dried at 105
for 1 hour, not more than 3 mg of residue remains (0.06%).
Limit of acetaldehyde
Place 100 mL of water in a 250-mL conical flask, add 5.0 mL of Paraldehyde, and shake the mixture gently until solution is complete. Add 5 mL of hydroxylamine hydrochloride solution (3.5 in 100). Shake the mixture gently for 30 seconds, add
methyl orange TS, and titrate immediately with 0.50 N sodium hydroxide. Perform a blank titration: the difference between the titers does not exceed 1 mL of 0.50 N sodium hydroxide (0.4%).