USP Nabumetone RS— Do not dry. Keep container tightly closed. Store in a cold place.

USP Nabumetone Related Compound A RS [1-(6-methoxy-2-naphthyl)-but-1-en-3-one] (C15H14O2 226.27) —Do not dry. Keep container tightly closed. Protect from light. Store in a refrigerator.

USP Nadolol RS— Do not dry. Keep container tightly closed.

USP Nafcillin Sodium RS— Do not dry before using. Keep container tightly closed. Store in a cold place.

USP Naftifine Hydrochloride RS— Dry over phosphorous pentoxide at 105 for 4 hours before using. Keep container tightly closed.

USP Nalidixic Acid RS— Dry portion at 105 for 2 hours before using. Keep container tightly closed.

USP Nalorphine Hydrochloride RS— Dry portion in vacuum at 100 for 2 hours before using. Keep container tightly closed. Protect from light.

USP Naloxone RS— Dry portion at 105 to constant weight before using. Keep container tightly closed. Protect from light.

USP Naltrexone RS— Do not dry. Keep container tightly closed. Protect from light.

USP Naltrexone Related Compound A RS [N-(3-butenyl)-noroxymorphone hydrochloride] (C20H23NO4·HCl 377.87) —Do not dry before using. Keep container tightly closed and protected from light.

USP Nandrolone RS— Do not dry before using. Keep container tightly closed and protected from light, and store in a refrigerator.

USP Nandrolone Decanoate RS— Dry portion in vacuum over silica gel for 4 hours before using. Keep container tightly closed. Protect from light. Store in a freezer.

USP Nandrolone Phenpropionate RS— Dry portion in a suitable vacuum drying tube, using phosphorus pentoxide as the desiccant, at 80 for 3 hours before using. Keep container tightly closed. Protect from light.

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

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

USP Naproxen Sodium RS— Dry portion in vacuum at 105 for 3 hours before using. Keep container tightly closed.

USP Narasin RS.

USP Naratriptan Hydrochloride RS —Do not dry. Keep container tightly closed. Protect from light. Store in a freezer.

USP Naratriptan Related Compound A RS [3-(1-methylpiperidin-4-yl)-1H-indole hydrochloride] (C14H18N2 · HCl 250.8)— Do not dry.

USP Naratriptan Related Compound B RS [2-[3-(1-methyl-1,2,3,6-tetrahydropyridin-4-yl)-1H-indol-5-yl]ethanesulfonic acid methylamide oxalate] (C17H23N3O2S · C2H2O4 423.5) —Do not dry.

USP Naratriptan Resolution Mixture RS— A mixture of naratriptan hydrochloride with approximately 1% of naratriptan related compound A [3-(1-methylpiperidin-4-yl)-1H-indole hydrochloride] and naratriptan related compound B [2-[3-(1-methyl-1,2,3,6-tetrahydropyridin-4-yl)-1H-indole-5-yl]ethanesulfonic acid methylamide oxalate].

USP Natamycin RS— Do not dry before using. Keep container tightly closed. Protect from light. Store in a cold place.

USP Near-Infrared Calibrator RS. USP29

USP Neomycin Sulfate 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 Neostigmine Bromide RS— Dry portion at 105 for 3 hours before using. Keep container tightly closed.

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

USP Neotame RS. USP29

USP Neotame Related Compound A RS [N-[3,3-dimethylbutyl)-L--aspartyl]-L-phenylalanine]. USP29

USP Netilmicin Sulfate RS— Do not dry before using; determine the volatiles content by heating a separate 100-mg portion at 110 at a pressure of 5 mm of mercury or less for 3 hours. Keep container tightly closed. Protect from light. Store in a freezer.

USP Nevirapine Anhydrous RS— Do not dry. Keep container tightly closed.

USP Nevirapine Hemihydrate RS— Do not dry. Keep container tightly closed.

USP Nevirapine Related Compound A RS [5,11-dihydro-6H-11-ethyl-4-methyl-dipyrido[3,2-b:2¢,3¢-e][1,4]diazepin-6-one] (C14H14N4O 254.29)— Do not dry. Keep container tightly closed.

USP Nevirapine Related Compound B RS [5,11-dihydro-4-methyl-6H-dipyrido[3,2-b:2¢,3¢-e][1,4]diazepin-6-one] (C12H10N4O 226.23)— Do not dry. Keep container tightly closed.

USP Niacin RS— Do not dry. Keep container tightly closed.

USP Niacinamide RS— Dry portion over silica gel for 4 hours before using. Keep container tightly closed.

USP Nicotine Bitartrate Dihydrate RS— Do not dry; determine the water content titrimetrically at time of use for quantitative analyses. Keep container tightly closed.

USP Nifedipine RS— Do not dry. Keep container tightly closed. Avoid exposure to light. Handle with care.

USP Nifedipine Nitrophenylpyridine Analog RS [dimethyl 4-(2-nitrophenyl)-2,6-dimethylpyridine-3,5-dicarboxylate] (C17H16N2O6 344.33) —Do not dry. Keep container tightly closed. Protect from light.

USP Nifedipine Nitrosophenylpyridine Analog RS [dimethyl 4-(2-nitrosophenyl)-2,6-dimethylpyridine-3,5-dicarboxylate] (C17H16N2O5 328.33) —Do not dry. Keep container tightly closed. Protect from light.

USP Nimodipine RS.

USP Nimodipine Related Compound A RS [(2-methoxyethyl-1-methylethyl-2,6-dimethyl-4-(3-nitrophenyl)pyridine-3,5-dicarboxylate] (C21H25N2O7 416.42).

USP Nitrofurantoin RS— Dry portion at 140 for 30 minutes before using. Keep container tightly closed. Protect from light.

USP Nitrofurantoin Related Compound A RS [N-(aminocarbonyl)-N-[([5-nitro-2-furanyl]methylene)amino]glycine] —Do not dry. Keep container tightly closed. Protect from light.USP29

USP Nitrofurazone RS— Dry portion at 105 for 1 hour before using. Keep container tightly closed. Protect from light. Avoid exposure to direct sunlight, to strong fluorescent lighting, to excessive heat, and to alkaline materials.

USP Nitrofurazone Related Compound A RS [5-nitro-2-fufuraldazine] (C10H6N4O6 278.18) —Dry portion at 105 for 1 hour before using. Keep container tightly closed. Protect from light.

USP Nitrofurfural Diacetate RS (C9H9NO7 243.17) —Do not dry. Keep container tightly closed. Protect from light.

USP Nitrogen RS.

USP 5-Nitro-2-furfuraldazine RS— (NAME CHANGE) See USP Nitrofurazone Related Compound A RS.

USP Diluted Nitroglycerin RS— [Caution—Handle with care; may be exploded by percussion or excessive heat. ] Do not dry; each ampul contains approximately 200 mg of a 1.00% solution (w/w) of nitroglycerin in propylene glycol. Store unopened ampuls at 4; allow to equilibrate to room temperature before opening ampul. Once opened, protect from moisture and light, and use promptly. Discard any unused portion.

USP Nitrous Oxide RS.

USP Nizatidine RS— Dry portion at 100 for 1 hour before using. Keep container tightly closed and protected from light.

USP Nonoxynol 9 RS— Do not dry. Once opened, take precautions against contact with air. Keep container tightly closed.

USP Nordazepam RS [7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzodiazepin-2-one] (C15H11ClN2O 270.72) —Do not dry before using. Keep container tightly closed. Protect from light.

USP Norepinephrine Bitartrate RS— Do not dry. This is the monohydrate form of norepinephrine bitartrate. Keep container tightly closed. Protect from light.

USP Norethindrone RS— Do not dry. Keep container tightly closed.

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

USP Norethynodrel RS— Do not dry before using. Keep container tightly closed.

USP Norfloxacin RS— Dry portion in vacuum at a pressure not exceeding 5 mm of mercury at 100 for 2 hours before using. Keep container tightly closed. Protect from light.

USP Norgestimate RS— Dry a portion at 105 for 3 hours. Keep containers tightly closed.

USP Norgestrel RS— Do not dry. Keep container tightly closed.

USP Noroxymorphone Hydrochloride RS— Do not dry before using. Keep container tightly closed. Protect from light.

USP Norphenylephrine Hydrochloride RS.

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

USP Noscapine RS— Do not dry; determine the water content titrimetrically at time of use. Keep container tightly closed.

USP Novobiocin RS— Dry portion in vacuum at a pressure not exceeding 5 mm of mercury at 100 for 4 hours before using. Keep container tightly closed. Protect from light. Store in a cold place.

USP Nystatin RS— Dry portion in vacuum at a pressure not exceeding 5 mm of mercury at 40 for 2 hours before using. Keep container tightly closed. Protect from light. Store in a freezer.