USP Labetalol Hydrochloride RS— Dry portion in vacuum at 105 for 4 hours before using. Keep container tightly closed. Protect from light.

USP Lactase RS— Do not dry before using. Keep container tightly closed. Store in a refrigerator. Before opening, allow to attain room temperature. Protect from air and humidity after opening.

USP Lactitol RS.

USP Anhydrous Lactose RS— Dry portion at 80 for 2 hours before using. Keep container tightly closed.

USP Lactose Monohydrate RS— For identification test, dry a portion at 80 for 2 hours. For quantitative use, determine the water content titrimetrically at the time of use. Keep container tightly closed.

USP Lactulose RS— Dry portion at 70 for 4 hours before using. Keep container tightly closed. Store between 2 and 30.

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

USP Lamivudine Resolution Mixture A RS— Do not dry. Keep container tightly closed. Protect from light. Store in a freezer.

USP Lamivudine Resolution Mixture B RS— Do not dry. Keep container tightly closed. Protect from light, and store at controlled room temperature.

USP Lanolin RS— Keep container tightly closed, and store at controlled room temperature.

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

USP Lansoprazole RS (C16H14F3N3O2S 369.36) —Do not dry. Keep container tightly closed. Protect from light. Store in a cold place.

USP Lansoprazole Related Compound A RS [2-[[[3-methyl-4-(2,2,2-trifluoroethoxy)-2-pyridyl]methyl]sulfonyl]benzimidazole] (C16H14F3N3O3S 385.36) —Do not dry. Keep container tightly closed. Protect from light. Store in a cold place.

USP Lauroyl Polyoxylglycerides RS— Store in original container and prevent exposure to air, heat, and moisture.USP29

USP Letrozole RS— Do not dry.

USP Letrozole Related Compound A RS [4,4¢-(1H-1,3,4-triazol-1-ylmethylene)dibenzonitrile] (C17H11N5 285.31) —Do not dry. Keep container tightly closed. Protect from light.

USP L-Leucine RS— Do not dry before using. Keep container tightly closed.

USP Leucovorin Calcium RS— [NOTE—This material is extremely hygroscopic.] Do not dry; determine the water content titrimetrically at time of use for quantitative analyses. Keep container tightly closed. Protect from light.

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

USP Levmetamfetamine RS— Do not dry before using. Keep container tightly closed and protected from light.

USP Levobunolol Hydrochloride RS— Dry portion in vacuum over phosphorus pentoxide in a suitable drying tube at 110 for 4 hours before using. Keep container tightly closed and protected from light.

USP Levocarnitine RS— For quantitative use, determine the water content titrimetrically at the time of use. For IR identification use, dry portion at 50 in vacuum for 5 hours. Keep container tightly closed. This material is extremely hygroscopic.

USP Levocarnitine Related Compound A RS [2-propen-1-aminium, 3-carboxy-N,N,N-trimethyl-, chloride] (C7H14ClNO2 179.65) —Do not dry. Keep container tightly closed. Store in a dry place.

USP Levodopa RS— Dry portion at 105 for 4 hours before using. Keep container tightly closed. Protect from light. Store in a dry place and prevent exposure to excessive heat.

USP Levodopa Related Compound A RS [3-(3,4,6-trihydroxyphenyl)alanine] (C9H11NO5 213.19) —Do not dry. Keep container tightly closed and protected from light. Store in a cool, dry place.

USP Levodopa Related Compound B RS [3-methoxytyrosine] (C10H13NO4 211.22)— Do not dry. Keep container tightly closed. Protect from light. Store in a cool, dry place.

USP Levonordefrin RS— Dry portion in vacuum at 60 for 15 hours before using. Keep container tightly closed.

USP Levorphanol Tartrate RS— This is the dihydrate form. Do not dry; determine the water content titrimetically at the time of use. Keep container tightly closed.

USP Levothyroxine RS— Use without drying; correct for moisture, determined by drying a separate portion in vacuum at 60 for 4 hours. Keep container tightly closed and protected from light.

USP Lidocaine RS— Dry portion in vacuum over silica gel for 24 hours before using. Keep container tightly closed.

USP Lincomycin Hydrochloride RS— Do not dry. This is the monohydrate form of lincomycin hydrochloride. Keep container tightly closed. Protect from light. Store in a cold place.

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

USP Linoleoyl Polyoxylglycerides RS— Store in original container, and prevent exposure to air, heat, and moisture.

USP Liothyronine RS— Do not dry before using. Correct for moisture, determined by drying a separate portion in vacuum at 60 for 3 hours.USP29 Keep container tightly closed. Protect from light. Store in a refrigerator.USP29

USP Alpha Lipoic Acid RS.

USP Lisinopril RS— This material is the dihydrate form of Lisinopril. Do not dry; determine the water content titrimetrically at time of use for quantitative analyses. Keep container tightly closed.

USP Lithium Carbonate RS— Dry portion at 200 for 4 hours before using. Keep container tightly closed. Store in a cool place.

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

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

USP Loracarbef L-Isomer RS— Do not dry before using. Keep container tightly closed, protected from light, and store in a cold place.

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

USP Loratadine Related Compound A RS [8-chloro-6,11-dihydro-11(4-piperidylidene)-5H-benzo[5,6]cyclohepta[1,2-b] pyridine] (C19H19ClN2 310.83)— Do not dry. Keep container tightly closed. Protect from light.

USP Loratadine Related Compound B RS [8-chloro-6,11-dihydro-11(N-methyl-4-piperinylidene)-5H-benzo[5,6]cyclohepta[1,2-b] pyridine] (C20H21ClN2 324.88)— Do not dry. Keep container tightly closed. Protect from light.

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

USP Lorazepam Related Compound A RS [7-chloro-5-(o-chlorophenyl)-1,3-dihydro-3-acetoxy-2H-1,4-benzodiazepin-2-one] (C17H12 Cl2N2O3 363.20) —Do not dry. Keep container tightly closed and protected from light.

USP Lorazepam Related Compound B RS [2-amino-2¢,5-dichlorobenzophenone] (C13H9ClNO 266.13) —Do not dry before using. Keep container tightly closed and protected from light.

USP Lorazepam Related Compound C RS [6-chloro-4-(o-chlorophenyl)-2-quinazolinecarboxaldehyde] (C15H8Cl2N2O 303.15) —Do not dry before using. Keep container tightly closed. Protect from light.

USP Lorazepam Related Compound D RS [6-chloro-4-(o-chlorophenyl)-2-quinazolinecarboxylic acid] (C15H8Cl2N2O2 319.15) — Do not dry before using. Keep container tightly closed. Protect from light.

USP Lorazepam Related Compound E RS [6-chloro-4-(o-chlorophenyl)-2-quinazoline methanol] (C15H10Cl2N2O 305.16) —Do not dry before using. Keep container tightly closed. Protect from light.

USP Lovastatin RS— Do not dry; use as is. Keep container tightly closed, and store in a freezer under nitrogen.

USP Lovastatin Related Compound A RS [dihydro-lovastatin] [butanoic acid, 2-methyl-, 1,2,3,4,4a,7,8,8a-octahydro-3,7-dimethyl-8-[2(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)-ethyl]-1-naphthalenyl ester, [1S-[1(R*),3,7,8(2S*,4S*),-8]]-] (C24 H38O5 406.56) —Do not dry. This material is hygroscopic. Keep container tightly closed. Protect from light. Store in a refrigerator.

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

USP Lutein RS— Do not dry. Keep container tightly closed, and store under nitrogen in a cool place. Protect from light.

USP Lycopene RS .

USP L-Lysine Acetate RS— Do not dry. Keep container tightly closed.

USP L-Lysine Hydrochloride RS— Dry portion at 105 for 3 hours before using. This is the monohydrochloride form. Keep container tightly closed.