USP Acebutolol Hydrochloride RS—
Dry portion at 105

for 3 hours before using. Keep container tightly closed.
USP Acepromazine Maleate RS—
Dry portion at 105

for 4 hours before using. Keep container tightly closed and protected from light.
USP Acesulfame Potassium RS—
Do not dry. Keep container tightly closed.
USP Acetaminophen RS—
Dry portion over silica gel for 18 hours before using. Keep container tightly closed and protected from light.
USP Acetanilide Melting Point RS—
Dry portion over sulfuric acid for 16 hours before using. When melted by the capillary tube method,
Class Ia in the general chapter
Melting Range or Temperature
741
, the observed range falls within the indicated acceptance range. Keep container tightly closed.
USP Acetazolamide RS—
Dry portion at 105

for 4 hours before using. Keep container tightly closed.
USP Acetohexamide RS—
Dry portion at 105

for 3 hours before using. Keep container tightly closed.
USP Acetohydroxamic Acid RS—
Dry portion over phosphorus pentoxide for 16 hours before using. Keep container tightly closed, and store in a desiccator in a cool place.
USP
-d-2-Acetoxy-4-dimethylamino-1,2-diphenyl-3-methylbutane RS—
(NAME CHANGE) See
USP Propoxyphene Related Compound B RS.
USP Acetylcholine Chloride RS
—Dry portion at 105

for 3 hours before using. Once opened, store in a desiccator, and keep container tightly closed. This material is extremely hygroscopic.
USP Acetylcysteine RS
—Dry portion at a pressure of about 50 mm of mercury at 70

for 4 hours before using. Keep container tightly closed.
USP Acetyltributyl Citrate RS
—Do not dry before using. After opening the ampul, keep the material in a tightly closed container.
USP Acetyltriethyl Citrate RS
—Do not dry before using. After opening the ampul, keep the material in a tightly closed container.
USP Acyclovir RS
—Do not dry; determine the water content titrimetrically at the time of use for quantitative analyses. Keep container tightly closed.
USP Adenine RS
—Dry portion at 110

for 4 hours before using. Keep container tightly closed and protected from light.
USP Adenosine RS
—Keep container tightly closed and protected from light.
USP Adipic Acid RS—
Dry portion at 105

to constant weight before using. Keep container tightly closed.
USP Agigenin RS
—Do not dry before using. Keep container tightly closed. Protect from light. Store in a freezer.
Add the following:
USP Agnuside RS
—This material is hygroscopic. Keep container tightly closed. Protect from light. Store in a desiccator.
USP29
USP Air–Helium RS.
USP L-Alanine RS
—Dry portion at 105

for 3 hours before using. Keep container tightly closed.
USP Albendazole RS
—Dry portion at 105

for 4 hours before using. Keep container tightly closed.
USP Albuterol RS
—Do not dry before using. Keep container tightly closed and protected from light.
USP Albuterol Sulfate RS
—Do not dry before using. Keep container tightly closed and protected from light.
USP Alclometasone Dipropionate RS
—Do not dry before using. Keep container tightly closed.
USP Alcohol RS—
After opening ampul, store the unused portion in a tightly closed container. Protect from light. This material is hygroscopic.
USP Dehydrated Alcohol RS—
After opening ampul, store the unused portion in a tightly closed container. Protect from light. This material is hygroscopic.
USP Alcohol Determination—Acetonitrile RS
—Acetonitrile in water. Dispose of unused portion after opening.
USP Alcohol Determination—Alcohol RS
—Alcohol solution in water. Dispose of unused portion after opening.
USP Alendronate Sodium RS
—Do not dry. This is the trihydrate form of alendronate sodium. Keep container tightly closed. After opening, store in a desiccator at room temperature.
USP Alfentanil Hydrochloride RS.
USP Allantoin RS—
Do not dry. Keep container tightly closed.
USP Alliin RS
—Do not dry before using. Keep container tightly closed, and store in a refrigerator. After opening, store the container in a desiccator in a refrigerator.
USP Allopurinol RS
—Dry portion in vacuum at 105

for 5 hours before using. Keep container tightly closed.
USP Allopurinol Related Compound A RS
[3-amino-4-carboxamidopyrazole hemisulfate
]
(C
4H
6N
4O)
2·H
2SO
4

350.32)
—Dry portion in vacuum at 105

for 3 hours before using. Keep container tightly closed.
USP S-Allyl-L-Cysteine RS
—Do not dry before using. Keep container tightly closed. Store in a freezer.
USP Alprazolam RS
—Do not dry before using. Keep container tightly closed.
USP Alprostadil RS
—Do not dry before using. Keep container tightly closed, and store in a freezer.
USP Alteplase RS.
USP Altretamine RS
—Do not dry before using. Determine the water content titrimetrically at the time of use. Keep container tightly closed.
USP Dried Aluminum Hydroxide Gel RS
—Do not dry before using. Keep container tightly closed.
USP Amantadine Hydrochloride RS
—Do not dry before using. Keep container tightly closed.
USP Amcinonide RS
—Do not dry before using. Keep container tightly closed. Store in a refrigerator.
USP Amifostine RS
—Do not dry.
USP Amifostine Disulfide RS
[1,3-propanediamine,
N,N-(dithiodi-2,1 ethanediyl)bis, tetrahydrochloride
]
(C
10H
30N
4S
2Cl
4

412.32)
—Do not dry. Keep container tightly closed. Store in a freezer.
USP Amifostine Thiol RS
[ethanethiol, 2-[(3-aminopropyl)amino]-, dihydrochloride
]
(C
5H
16N
2SCl
2

207.17)
—Do not dry. Keep container tightly closed. Store in a freezer.
USP Amikacin RS—
Do not dry before using. Keep container tightly closed, protected from light, and store in a cold place.
USP Amiloride Hydrochloride RS—
Using thermogravimetric analysis (see
Thermal Analysis
891
), heat a 10-mg portion, accurately weighed, at 10

per minute between ambient temperature and 225

under nitrogen flowing at 40 mL per minute. From the thermogram, determine the accumulated loss in weight between ambient temperature and about 200

on the plateau. Keep container tightly closed.
USP Amiloxate RS [isoamyl methoxycinnamate].
USP Aminobenzoate Potassium RS—
Dry portion at 105

for 2 hours before using. Keep container tightly closed and protected from light.
USP Aminobenzoic Acid RS—
Do not dry. Keep container tightly closed. Protect from light.
USP Aminobutanol RS
(C
4H
11NO

89.14)
—This material is hygroscopic. After opening ampul, store in tightly closed container. Do not dry; determine the water content titrimetrically at the time of use.
USP Aminocaproic Acid RS—
Dry portion at 105

for 30 minutes before using. Keep container tightly closed.
USP N-(Aminocarbonyl)-N-[([5-nitro-2-furanyl]-methylene)-amino]-glycine RS—
Do not dry before using.
USP 2-Amino-5-chlorobenzophenone RS
(C
13H
10ClNO

231.68)
—Keep container tightly closed and protected from light. Dry portion over silica gel for 4 hours before using.
USP 3-Amino-6-chloro-1-methyl-4-phenylcarbostyril RS—
(NAME CHANGE) See USP Diazepam Related Compound B RS.
USP 3-Amino-2,4,6-triiodobenzoic Acid RS
(C
7H
4I
3NO
2

514.83)
—Dry portion at 105

for 4 hours before using. Keep container tightly closed and protected from light.
USP 5-Amino-2,4,6-triiodo-N-methylisophthalamic Acid RS
(C
9H
7I
3N
2O
3

571.88)
—Dry portion at 105

for 4 hours before using. Keep container tightly closed and protected from light.
USP Aminoglutethimide RS—
Dry portion at 105

to constant weight before using. Keep container tightly closed.
USP m-Aminoglutethimide RS—
Do not dry before using. Keep container tightly closed.
USP Aminohippuric Acid RS—
Do not dry before using. Keep container tightly closed and protected from light. Material will discolor if exposed to light and air.
USP 5-Aminoimidazole-4-carboxamide Hydrochloride RS
(C
4 H
6N
4O·HCl

162.58)
—Do not dry before using. Keep container tightly closed, protected from light, and store in a refrigerator.
USP Aminopentamide Sulfate RS—
Dry at 105

for 4 hours before using.
Add the following:
USP 4-Aminophenol RS.
USP29
USP m-Aminophenol RS—
Do not dry before using. Keep container tightly closed, protected from light, and store in a cold place.
USP Aminosalicylic Acid RS—
Dry portion in vacuum at 50

for 1 hour before using. Keep container tightly closed, protected from light, and store at a temperature not exceeding 30

.
USP Amitraz RS—
Do not dry. Keep container tightly closed. Protect from light.
USP Amitriptyline Hydrochloride RS—
Dry portion at a pressure not exceeding 5 mm of mercury at 60

to constant weight before using. Keep container tightly closed.
USP Ammonio Methacrylate Copolymer, Type A RS—
Dry portion in vacuum at 80

for 5 hours before using. Keep container tightly closed.
USP Ammonio Methacrylate Copolymer, Type B RS—
Dry portion in vacuum at 80

for 5 hours before using. Keep container tightly closed.
USP Ammonium Chloride RS—
Dry over silica gel for 4 hours. This material is hygroscopic. Keep container tightly closed. Store at room temperature.
USP Amobarbital RS—
Dry portion at 105

for 4 hours before using. Keep container tightly closed.
USP Amodiaquine Hydrochloride RS—
Do not dry; determine the water content titrimetrically at the time of use. Keep container tightly closed.
USP Amoxapine RS—
Dry portion at 105

for 4 hours before using. Keep container tightly closed.
USP Amoxicillin RS—
Do not dry before using. This is a trihydrate form of amoxicillin. Keep container tightly closed. Protect from light, and store in a freezer.
USP Amphotericin B RS—
Dry portion in vacuum at a pressure not exceeding 5 mm of mercury at 60

for 3 hours before using. Keep container tightly closed. Protect from light. Store in a cold place.
USP Ampicillin RS—
This is the anhydrous form of ampicillin. Before using, dry portion to constant weight in vacuum over phosphorus pentoxide at room temperature. Keep container tightly closed. Store in a cool, dry place.
USP Ampicillin Sodium RS—
Do not dry before using. Hygroscopic. Keep container tightly closed. Store in a cool, dry place.
USP Ampicillin Trihydrate RS—
Do not dry before using. Keep container tightly closed and protected from light. Store in a cold, dry place.
USP Amprolium RS—
Dry portion at a pressure not exceeding 5 mm of mercury at 100

for 3 hours before using. Keep container tightly closed.
USP Anileridine Hydrochloride RS—
Dry portion at a pressure below 5 mm of mercury at 100

for 2 hours before using. Keep container tightly closed. Protect from light.
USP Antazoline Phosphate RS—
Dry portion at 105

for 4 hours before using. Keep container tightly closed.
USP Anthralin RS—
Do not dry before using. Keep container tightly closed, and store in a cool place. Protect from light.
USP Antipyrine RS—
Dry portion at 60

for 2 hours before using. Keep container tightly closed.
USP Apigenin-7-Glucoside RS—
Do not dry. For quantitative USP applications use a value of 0.88 mg of apigenin-7-glucoside for each mg of this standard on the as-is basis. Keep container tightly closed, protected from light, and store in a freezer.
USP Apomorphine Hydrochloride RS—
Dry portion at 105

for 2 hours before using. Keep container tightly closed. Protect from light.
USP Apraclonidine Hydrochloride RS—
Dry portion in vacuum at 105

for 3 hours before using. Keep container tightly closed. Protect from light.
USP L-Arginine RS—
Dry portion at 105

for 3 hours before using. Keep container tightly closed.
USP Arginine Hydrochloride RS—
Do not dry. Keep container tightly closed.
USP Arsanilic Acid RS—
Do not dry. Keep container tightly closed.
USP Ascorbic Acid RS—
Do not dry. Keep container tightly closed and protected from light.
Delete the following:
USP Asparagine RS.
USP29
Add the following:
USP Asparagine Anhydrous RS.
USP29
Add the following:
USP Asparagine Monohydrate RS.
USP29
USP Aspartame RS—
Do not dry before using. Keep container tightly closed. Protect from light. Store in a desiccator.
USP Aspartame Acesulfame RS—
Do not dry. Keep container tightly closed.
USP Aspartame Related Compound A RS
[5-benzyl-3,6-dioxo-2-piperazineacetic acid
]
(C
13H
14N
2O
4

262.27)
—Do not dry. Keep container tightly closed and protected from light.
USP Aspartic Acid RS—
Do not dry. Store at room temperature.
USP Aspirin RS—
Dry portion over silica gel for 5 hours before using. Keep container tightly closed.
USP Astemizole RS—
Dry at 105

in vacuum for 4 hours before using. Keep container tightly closed.
USP Atenolol RS—
Dry portion at 105

for 3 hours before using. Keep container tightly closed.
USP Atovaquone RS—
Do not dry before using.
USP Atovaquone Related Compound A RS
[cis-2[4-(4-chlorophenyl)cyclohexyl]-3-hydroxy-1,4-naphthoquinone]—
Do not dry before using.
USP Atracurium Besylate RS—
Do not dry; determine the water content titrimetrically at the time of use. Keep container tightly closed, and store in a cold place.
USP Atropine Sulfate RS—
Do not dry before using. Determine the water content titrimetrically at the time of use. Keep container tightly closed. Protect from light.
USP Aurothioglucose RS—
Dry portion over phosphorus pentoxide for 24 hours before using. Keep container tightly closed. Protect from light.
USP Avobenzone RS—
Dry portion in vacuum at 70

for 4 hours before using. For quantitative applications use a value of 0.994 mg of avobenzone per mg on the dried basis. Keep container tightly closed.
USP Azaerythromycin A RS—
Do not dry before using. Keep container tightly closed.
USP Azaperone RS—
Dry portion in vacuum at 60

for 4 hours before using. Keep container tightly closed. Protect from light.
USP Azatadine Maleate RS—
Do not dry. Keep container tightly closed.
USP Azathioprine RS—
Dry portion in vacuum at 105

for 5 hours before using. Keep container tightly closed. Protect from light.
USP Azithromycin RS—
Do not dry before using. Keep container tightly closed, and store in a freezer.
USP Azo-aminoglutethimide RS—
Dry portion at 105

for 2 hours before using. Keep container tightly closed. Protect from light.
USP Aztreonam RS—
Do not dry before using. Keep container tightly closed. Protect from light. Store in a cold place.
USP Aztreonam E-Isomer RS—
Do not dry before using. Keep container tightly closed, protected from light, air, and moisture, and store in a refrigerator.
USP Open Ring Aztreonam RS
(C
18H
19N
5O
9S
2

453.46)
—Do not dry before using. Keep container tightly closed, protected from light, and store in a freezer. This material is extremely hygroscopic.