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Technical details about MolPort-002-137-856, learn more about the structure, uses, toxicity, action, side effects and more

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2D Structure
Also known as: 58-56-0, Pyridoxine hcl, Pyridoxol hydrochloride, Vitamin b6, Vitamin b6 hydrochloride, Pyridoxine chloride
Molecular Formula
C8H12ClNO3
Molecular Weight
205.64  g/mol
InChI Key
ZUFQODAHGAHPFQ-UHFFFAOYSA-N
FDA UNII
68Y4CF58BV

The 4-methanol form of VITAMIN B 6 which is converted to PYRIDOXAL PHOSPHATE which is a coenzyme for synthesis of amino acids, neurotransmitters (serotonin, norepinephrine), sphingolipids, aminolevulinic acid. Although pyridoxine and Vitamin B 6 are still frequently used as synonyms, especially by medical researchers, this practice is erroneous and sometimes misleading (EE Snell; Ann NY Acad Sci, vol 585 pg 1, 1990).
1 2D Structure

2D Structure

2 Identification
2.1 Computed Descriptors
2.1.1 IUPAC Name
4,5-bis(hydroxymethyl)-2-methylpyridin-3-ol;hydrochloride
2.1.2 InChI
InChI=1S/C8H11NO3.ClH/c1-5-8(12)7(4-11)6(3-10)2-9-5;/h2,10-12H,3-4H2,1H3;1H
2.1.3 InChI Key
ZUFQODAHGAHPFQ-UHFFFAOYSA-N
2.1.4 Canonical SMILES
CC1=NC=C(C(=C1O)CO)CO.Cl
2.2 Other Identifiers
2.2.1 UNII
68Y4CF58BV
2.3 Synonyms
2.3.1 MeSH Synonyms

1. Pyridoxin

2. Pyridoxine

3. Pyridoxol

4. Pyridoxol Hydrochloride

5. Rodex

2.3.2 Depositor-Supplied Synonyms

1. 58-56-0

2. Pyridoxine Hcl

3. Pyridoxol Hydrochloride

4. Vitamin B6

5. Vitamin B6 Hydrochloride

6. Pyridoxine Chloride

7. Hexa-betalin

8. Alestrol

9. Becilan

10. Benadon

11. Hexavibex

12. Hexermin

13. Hexobion

14. Pyridipca

15. Beesix

16. Pydox

17. Adermine Hydrochloride

18. Campoviton 6

19. Aderoxine

20. Pyridoxinium Chloride

21. Aderomine Hydrochloride

22. Hexabione Hydrochloride

23. Pyridoxin Hydrochloride

24. Pyridoxinum Hydrochloricum

25. 4,5-bis(hydroxymethyl)-2-methylpyridin-3-ol Hydrochloride

26. Bendectin

27. 3,4-pyridinedimethanol, 5-hydroxy-6-methyl-, Hydrochloride

28. Pyridoxol, Hydrochloride

29. Pyridoxine (hydrochloride)

30. 5-hydroxy-6-methyl-3,4-pyridinedimethanol Hydrochloride

31. Mfcd00012807

32. 2-methyl-3-hydroxy-4,5-bis(hydroxymethyl)pyridine Hydrochloride

33. 3-hydroxy-4,5-dimethylol-alpha-picoline Hydrochloride

34. 5-hydroxy-6-methyl-3,4-pyridinedicarbinol Hydrochloride

35. 4,5-bis(hydroxymethyl)-2-methylpyridin-3-ol;hydrochloride

36. Bonasanit

37. (5-hydroxy-6-methylpyridine-3,4-diyl)dimethanol Hydrochloride

38. Nsc-36225

39. Adermin Hydrochloride

40. 5-hydroxy-6-methyl-3,4-pyridinedimethanol, Hydrochloride

41. 68y4cf58bv

42. Hexabetalin

43. Aderoxin

44. Godabion

45. Paxadon

46. Pyridox

47. Chebi:30961

48. Pyridoxine Hydrogen Chloride

49. 8064-77-5

50. Hexa-betalin (r)

51. Spondylonal

52. Rodex (r)

53. Pn Hcl

54. Pyridoxin Hydrochloride (vitamin B6 Hydrochloride)

55. Pyridoxine Monohydrochloride

56. Pyridoxol (hydrochloride);vitamin B6 (hydrochloride)

57. 4,5-bis(hydroxymethyl)-2-methyl-3-pyridinol Hydrochloride

58. Pyridoxine, Hydrochloride

59. 3,4-pyridinedimethanol, 5-hydroxy-6-methyl-, Hydrochloride (1:1)

60. Pyridoxinum Hydrochloricum (hungarian)

61. Smr000674613

62. Hexa-betalin (tn)

63. Nsc36225

64. Ccris 1903

65. Component Of Alestrol

66. Hsdb 1212

67. Tex Six T.r.

68. Clorhidrato De Piridoxina

69. Ncgc00164317-01

70. Vitamin B6-hydrochloride

71. Einecs 200-386-2

72. Nsc 36225

73. Unii-68y4cf58bv

74. Ai3-19016

75. Pyridoxine Hydrochloride [jan]

76. 3-hydroxy-4,5-dihydroxymethyl-2-methylpyridine Hydrochloride

77. Prestwick_925

78. Pyridoxine Hydrochloride [usp:jan]

79. Pyridoxini Hydrochloridum

80. 4,5-bis(hydroxymethyl)-3-hydroxy-2-methylpyridine Hydrochloride

81. Pyridoxol (hydrochloride)

82. Vitamin B6, Hydrochloride

83. Vitamin B6 (hydrochloride)

84. Dsstox_cid_10780

85. Dsstox_rid_79601

86. Dsstox_gsid_40792

87. Schembl42293

88. Mls001074329

89. Mls002153915

90. Pyridoxine Hcl [inci]

91. Pyridoxine Hcl [vandf]

92. Pyridoxine Hydrochloride, 98%

93. 3-hydroxy-4,5-dimethylol-.alpha.-picoline Hydrochloride

94. Chembl1200756

95. Dtxsid1040792

96. Hms1569n08

97. Amy37035

98. Hy-n0682

99. Tox21_302476

100. Pyridoxine Hydrochloride [mi]

101. S3113

102. 3-hydroxy-4,5-dimethylol-alpha-pic

103. Pyridoxine Hydrochloride (jp17/usp)

104. Pyridoxine Hydrochloride [fcc]

105. Akos015891679

106. Pyridoxine Hcl (vitamin B6) Solution

107. Ccg-220623

108. Cs-w020418

109. Pyridoxine Hydrochloride [hsdb]

110. 3, 5-hydroxy-6-methyl-, Hydrochloride

111. Pyridoxine Hydrochloride [mart.]

112. Pyridoxine Hydrochloride [vandf]

113. Ncgc00180946-01

114. Ncgc00256911-01

115. Pyridoxine Hydrochloride [usp-rs]

116. Pyridoxine Hydrochloride [who-dd]

117. Pyridoxine Hydrochloride [who-ip]

118. Pyridoxinum Hydrochloricum [hpus]

119. Ac-12024

120. As-11752

121. Sy061587

122. Wln: T6nj B1 Cq D1q E1q &gh

123. Pyridoxine Hydrochloride, >=98% (hplc)

124. Db-053225

125. Pyridoxine Hydrochloride, P.a., 98-102%

126. B2017

127. Ft-0631260

128. P0561

129. Pyridoxine Hydrochloride [green Book]

130. Sw197042-3

131. Tpn Component Pyridoxine Hydrochloride

132. Pyridoxine Hydrochloride [ep Impurity]

133. Pyridoxine Hydrochloride [orange Book]

134. D02179

135. H12039

136. Pyridoxine Hydrochloride [ep Monograph]

137. Pyridoxine Hydrochloride [usp Monograph]

138. Pyridoxine Hydrochloride Component Of Tpn

139. Pyridoxini Hydrochloridum [who-ip Latin]

140. Vitamin B6 (as Pyridoxine Hydrochloride)

141. Bendectin Component Pyridoxine Hydrochloride

142. Bonjesta Component Pyridoxine Hydrochloride

143. Diclectin Component Pyridoxine Hydrochloride

144. Diclegis Component Pyridoxine Hydrochloride

145. Pyridoxine Hydrochloride (b6), Analytical Standard

146. Pyridoxine Hydrochloride, Plant Cell Culture Tested

147. Q-201647

148. Sr-05000001644-4

149. Pyridoxine Hydrochloride Component Of Bendectin

150. Pyridoxine Hydrochloride Component Of Bonjesta

151. Q26841284

152. F0001-2400

153. Pyridoxine Hydrochloride, Saj Special Grade, >=98.0%

154. Pyridoxine Hydrochloride, Vetec(tm) Reagent Grade, 98%

155. Pyridoxine Hydrochloride, Meets Usp Testing Specifications

156. Pyridoxine Hydrochloride 1.0 Mg/ml In Methanol (as Free Base)

157. 3-hydroxy-4,5-bis(hydroxymethyl)-2-methylpyridine Hydrochloride

158. Pyridoxine Hydrochloride, Certified Reference Material, Tracecert(r)

159. Pyridoxine Hydrochloride, British Pharmacopoeia (bp) Reference Standard

160. Pyridoxine Hydrochloride, European Pharmacopoeia (ep) Reference Standard

161. Pyridoxin Hydrochloride (vitamin B6 Hydrochloride) 100 Microg/ml In Methanol

162. Pyridoxine Hydrochloride, Pharmaceutical Secondary Standard; Certified Reference Material

163. Pyridoxine Hydrochloride, United States Pharmacopeia (usp) Reference Standard

164. Pyridoxine Hcl (vitamin B6) Solution, 1.0 Mg/ml In Methanol (as Free Base), Ampule Of 1 Ml, Certified Reference Material

165. Pyridoxine Hydrochloride, Bioreagent, Suitable For Cell Culture, Suitable For Insect Cell Culture, Suitable For Plant Cell Culture

166. Pyridoxine Hydrochloride, Pharmagrade, Ep, Manufactured Under Appropriate Gmp Controls For Pharma Or Biopharmaceutical Production

2.4 Create Date
2004-09-16
3 Chemical and Physical Properties
Molecular Weight 205.64 g/mol
Molecular Formula C8H12ClNO3
Hydrogen Bond Donor Count4
Hydrogen Bond Acceptor Count4
Rotatable Bond Count2
Exact Mass205.0505709 g/mol
Monoisotopic Mass205.0505709 g/mol
Topological Polar Surface Area73.6 Ų
Heavy Atom Count13
Formal Charge0
Complexity142
Isotope Atom Count0
Defined Atom Stereocenter Count0
Undefined Atom Stereocenter Count0
Defined Bond Stereocenter Count0
Undefined Bond Stereocenter Count0
Covalently Bonded Unit Count2
4 Drug and Medication Information
4.1 Drug Information
1 of 2  
Drug NamePyridoxine hydrochloride
Drug LabelPyridoxine Hydrochloride Injection, USP is a sterile solution of pyridoxine hydrochloride in Water for Injection. Each mL contains 100 mg pyridoxine hydrochloride and 0.5% chlorobutanol anhydrous (chloral deriv.). pH adjusted with sodium hydroxid...
Active IngredientPyridoxine hydrochloride
Dosage FormInjectable
RouteInjection
Strength100mg/ml
Market StatusPrescription
CompanyFresenius Kabi Usa

2 of 2  
Drug NamePyridoxine hydrochloride
Drug LabelPyridoxine Hydrochloride Injection, USP is a sterile solution of pyridoxine hydrochloride in Water for Injection. Each mL contains 100 mg pyridoxine hydrochloride and 0.5% chlorobutanol anhydrous (chloral deriv.). pH adjusted with sodium hydroxid...
Active IngredientPyridoxine hydrochloride
Dosage FormInjectable
RouteInjection
Strength100mg/ml
Market StatusPrescription
CompanyFresenius Kabi Usa

4.2 Therapeutic Uses

DOSE: USUAL, ORAL OR PARENTERAL, PROPHYLACTIC, 2 MG ONCE A DAY; THERAPEUTIC, 5 TO 150 MG DAILY. DOSE FOR MALNUTRITION IS 5 TO 10 MG DAILY; FOR HYPEREMESIS GRAVIDUM & EMESIS OF RADIATION SICKNESS IS 10 TO 100 MG DAILY.

Osol, A. and J.E. Hoover, et al. (eds.). Remington's Pharmaceutical Sciences. 15th ed. Easton, Pennsylvania: Mack Publishing Co., 1975., p. 960


... MAY BE USED PROPHYLACTICALLY TO PREVENT PERIPHERAL NEURITIS IN PATIENTS TREATED WITH ISONIAZID. APPEARS TO AID IN DISSOLUTION OF RENAL STONES OF CALCIUM OXALATE ... INCR EXCRETION OF CALCIUM-CHELATING CITRIC ACID.

Osol, A. and J.E. Hoover, et al. (eds.). Remington's Pharmaceutical Sciences. 15th ed. Easton, Pennsylvania: Mack Publishing Co., 1975., p. 960


MEDICATION (VET): ... ANTIDOTAL IN MICE & DOGS TO CONVULSIVE EFFECTS OF RODENTICIDE CRIMIDINE.

Rossoff, I.S. Handbook of Veterinary Drugs. New York: Springer Publishing Company, 1974., p. 647


... INFANTS MAY EXHIBIT HYPERIRRITABILITY & EPILEPTIFORM CONVULSIONS DURING FIRST WK OF LIFE THAT PROMPTLY RESPOND TO ADMIN OF PYRIDOXINE. IF UNTREATED, PYRIDOXINE-RESPONSIVE ANEMIA & MENTAL RETARDATION MAY RESULT. /PYRIDOXINE/

American Medical Association, AMA Department of Drugs. AMA Drug Evaluations. 4th ed. Chicago: American Medical Association, 1980., p. 823


For more Therapeutic Uses (Complete) data for PYRIDOXINE HYDROCHLORIDE (22 total), please visit the HSDB record page.


4.3 Drug Warning

Pyridoxine is usually nontoxic; however, chronic admin of large dosages has been assoc with adverse neurologic effects. Nausea, headache, paresthesia, somnolence, & incr serum AST (SGOT) & decr serum folic acid concn have been reported. Burning or stinging at the injection site may occur following IM or subcutaneous injection of pyridoxine. Seizures have occurred following IV admin of very large doses. Allergic reactions have been reported occasionally in patients receiving the vitamin.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3319


Pyridoxine should not be used in patients with a history of sensitivity to the vitamin. According to one manufacturer, pyridoxine should not be administered iv to patients with heart disease.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3319


Maternal Medication usually Compatible with Breast-Feeding: B6 (pyridoxine): Reported Sign or Symptom in Infant or Effect on Lactation: None. /from Table 6/

Report of the American Academy of Pediatrics Committee on Drugs in Pediatrics 93 (1): 140 (1994)


Very large doses of pyridoxine have been reported to have a lactation-inhibiting effect. Using oral doses of 600 mg/day, lactation was successfully inhibited in 95% of patients within 1 week as compared to only 17% of placebo-treated controls. /Pyridoxine/

Briggs, G.G, R.K. Freeman, S.J. Yaffe. A Reference Guide to Fetal and Neonatal Risk. Drugs in Pregnancy and Lactation. 4th ed. Baltimore, MD: Williams & Wilkins 1994., p. 751


5 Pharmacology and Biochemistry
5.1 MeSH Pharmacological Classification

Vitamin B Complex

A group of water-soluble vitamins, some of which are COENZYMES. (See all compounds classified as Vitamin B Complex.)


5.2 FDA Pharmacological Classification
5.2.1 Pharmacological Classes
Vitamin B 6 [Chemical/Ingredient]; Vitamin B6 Analog [EPC]; Analogs/Derivatives [Chemical/Ingredient]
5.3 Absorption, Distribution and Excretion

THE FAT SOLUBLE VITAMINS A, D, & K ARE ABSORBED FROM SKIN, AS ARE LIPID INSOLUBLE VITAMINS, THIAMINE, RIBOFLAVIN, CALCIUM PANTOTHENATE, PYRIDOXINE. /PYRIDOXINE/

Hayes, W. J., Jr. Toxicology of Pesticides Baltimore: Williams & Wilkins, 1975., p. 149


... READILY ABSORBED FROM GI TRACT. ... EXCRETORY PRODUCT ... OF VITAMIN /WHEN IT IS FED TO MAN IS 4-PYRIDOXIC ACID. /PYRIDOXINE/

Hardman, J.G., L.E. Limbird, P.B. Molinoff, R.W. Ruddon, A.G. Goodman (eds.). Goodman and Gilman's The Pharmacological Basis of Therapeutics. 9th ed. New York, NY: McGraw-Hill, 1996., p. 1563


Pyridoxine, pyridoxal, and pyridoxamine are readily absorbed from the GI tract following oral administration; however, GI absorption may be diminished in patients with malabsorption syndromes or following gastric resection. Normal serum concentrations of pyridoxine are 30-80 ng/ml.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3318


Vitamin B6 is stored mainly in the liver with lesser amounts in muscle & brain. The total body store of vitamin B6 is estimated to be about 167 mg. Pyridoxal and pyridoxal phosphate, the principal forms of the vitamin present in blood, are highly protein bound. Pyridoxal crosses the placenta, & plasma concn in the fetus are 5 times > maternal plasma concn. The concn of vitamin B6 in milk is about 150 240 mg/mL following maternal intake of 2.5 5 mg of vitamin B6 daily. Following maternal intake of < 2.5 mg of vitamin B6 daily, vitamin B6 concn in milk averages 130 mg/mL.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3318


For more Absorption, Distribution and Excretion (Complete) data for PYRIDOXINE HYDROCHLORIDE (6 total), please visit the HSDB record page.


5.4 Metabolism/Metabolites

ALL THREE FORMS OF VITAMIN B6 /PYRIDOXINE, PYRIDOXAL, & PYRIDOXAMINE/ ARE CONVERTED TO PYRIDOXAL PHOSPHATE IN BODY; PYRIDOXAL IS CONVERTED TO PYRIDOXAL PHOSPHATE BY ENZYME, PYRIDOXAL KINASE ... . /PYRIDOXINE/

Gilman, A. G., L. S. Goodman, and A. Gilman. (eds.). Goodman and Gilman's The Pharmacological Basis of Therapeutics. 6th ed. New York: Macmillan Publishing Co., Inc. 1980., p. 1570


/4-PYRIDOXIC ACID/ ... FORMED BY ACTION OF HEPATIC ALDEHYDE OXIDASE ON FREE PYRIDOXAL. ADMIN OF PYRIDOXINE ... RESULTS IN INCR EXCRETION OF PYRIDOXAL ... FIRST TRANSFORMED, DIRECTLY OR INDIRECTLY, TO PYRIDOXAL, WHICH IS THEN OXIDIZED TO 4-PYRIDOXIC ACID ... . /PYRIDOXINE/

Gilman, A. G., L. S. Goodman, and A. Gilman. (eds.). Goodman and Gilman's The Pharmacological Basis of Therapeutics. 6th ed. New York: Macmillan Publishing Co., Inc. 1980., p. 1571


In erythrocytes, pyridoxine is converted to pyridoxal phosphate and pyridoxamine is converted to pyridoxamine phosphate. In the liver, pyridoxine is phosphorylated to pyridoxine phosphate and transaminated to pyridoxal and pyridoxamine which are rapidly phosphorylated. Riboflavin is required for the conversion of pyridoxine phosphate to pyridoxal phosphate. The principal forms of the vitamin in the blood are pyridoxal and pyridoxal phosphate.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3318


In humans, an exogenous source of vitamin B6, is required for amino acid metab; the vitamin is also involved in carbohydrate & lipid metab. Pyridoxine, pyridoxal, & pyridoxamine are converted to the active forms of the vitamin, pyridoxal phosphate & pyridoxamine phosphate, which act as coenzymes in a wide variety of reactions in intermed metab. The active forms of the vitamin are involved in transamination of amino acids & in the conversion of tryptophan to niacin. Pyridoxine appears to be essential in the synth of y aminobutyric acid (GABA) within the CNS & in the synth of heme. Pyridoxine deficiency results in the accum & urinary excretion of xanthurenic acid (an intermed metabolite of tryptophan) & in decr glutamic oxaloacetic transaminase activity in erythrocytes; measurement of either of these may be used to diagnose pyridoxine deficiency. For detn of xanthurenic acid excretion, an oral loading dose of 2 10 g of tryptophan is usually given; urine is collected for 8 hours & then analyzed for xanthurenic acid. Urinary excretion of vitamin B6 or 4 pyridoxic acid can also be analyzed to determine pyridoxine deficiency.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3318


In the liver pyridoxal is oxidized to 4-pyridoxic acid.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3318


5.5 Biological Half-Life

TRITIUM-LABELED PYRIDOXINE HYDROCHLORIDE WAS ADMIN TO RATS. ISOTOPE EXCRETION IN URINE OCCURRED WITH HALF-LIFE OF 40-228 DAYS AFTER THE SECOND DAY OF THE EXPT. THE ELIMINATION RATE OF PYRIDOXINE WAS NOT SIGNIFICANTLY AFFECTED BY PYRIDOXINE HYDROCHLORIDE INTAKE.

PMID:5947254 JOHANSSON S ET AL; AM J PHYSIOL 210 (5): 1086 (1966)


Biologic half-life of pyridoxine appears to be 15-20 days.

McEvoy, G.K. (ed.). American Hospital Formulary Service - Drug Information 2000.Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2000 (Plus Supplements)., p. 3319


5.6 Mechanism of Action

BRAIN GABA PRODN BEGAN TO RISE 7.5 MIN AFTER IP ADMIN OF 10 MG PYRIDOXINE HYDROCHLORIDE & CONTINUED FOR 40 MIN, THEN DECLINED.

PMID:1193274 ACKROYD B, SMITH WR D; BIOCHEM SOC TRANS 3 (5): 707 (1975)


NUTRITIONAL NEED FOR VITAMIN B6 IS BASED ON ITS COENZYME FUNCTION IN AN UNUSUALLY LARGE NUMBER OF METABOLIC REACTIONS. ... REQUIRED IN METABOLISM OF AMINO ACIDS, FATS & CARBOHYDRATES & FOR SYNTHESIS OF PHYSIOLOGIC REGULATORS SUCH AS NOREPINEPHRINE, SEROTONIN & HISTAMINE.

Furia, T.E. (ed.). CRC Handbook of Food Additives. 2nd ed. Cleveland: The Chemical Rubber Co., 1972., p. 90


PYRIDOXAL PHOSPHATE IS INVOLVED IN SEVERAL METABOLIC TRANSFORMATIONS OF AMINO ACIDS INCLUDING DECARBOXYLATION, TRANSAMINATION, & RACEMIZATION, AS WELL AS ENZYMATIC STEPS IN METABOLISM OF SULFUR-CONTAINING & HYDROXY AMINO ACIDS. /PYRIDOXINE/

Gilman, A.G., T.W. Rall, A.S. Nies and P. Taylor (eds.). Goodman and Gilman's The Pharmacological Basis of Therapeutics. 8th ed. New York, NY. Pergamon Press, 1990., p. 1539


PYRIDOXINE ... IS AN ESSENTIAL PART OF THE ENZYME GLYCOGEN PHOSPHORYLASE. /PYRIDOXINE/

Evaluations of Drug Interactions. 2nd ed. and supplements. Washington, DC: American Pharmaceutical Assn., 1976, 1978., p. 452


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