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2D Structure
Also known as: 77883-43-3, Cardura, Carduran, Alfadil, Cardular, Cardura xl
Molecular Formula
C24H29N5O8S
Molecular Weight
547.6  g/mol
InChI Key
VJECBOKJABCYMF-UHFFFAOYSA-N
FDA UNII
86P6PQK0MU

A prazosin-related compound that is a selective alpha-1-adrenergic blocker.
1 2D Structure

2D Structure

2 Identification
2.1 Computed Descriptors
2.1.1 IUPAC Name
[4-(4-amino-6,7-dimethoxyquinazolin-2-yl)piperazin-1-yl]-(2,3-dihydro-1,4-benzodioxin-3-yl)methanone;methanesulfonic acid
2.1.2 InChI
InChI=1S/C23H25N5O5.CH4O3S/c1-30-18-11-14-15(12-19(18)31-2)25-23(26-21(14)24)28-9-7-27(8-10-28)22(29)20-13-32-16-5-3-4-6-17(16)33-20;1-5(2,3)4/h3-6,11-12,20H,7-10,13H2,1-2H3,(H2,24,25,26);1H3,(H,2,3,4)
2.1.3 InChI Key
VJECBOKJABCYMF-UHFFFAOYSA-N
2.1.4 Canonical SMILES
COC1=C(C=C2C(=C1)C(=NC(=N2)N3CCN(CC3)C(=O)C4COC5=CC=CC=C5O4)N)OC.CS(=O)(=O)O
2.2 Other Identifiers
2.2.1 UNII
86P6PQK0MU
2.3 Synonyms
2.3.1 MeSH Synonyms

1. 1 (4-amino-6,7-dimethoxy-2-quinazolinyl)-4-((2,3-dihydro-1,4-benzodioxin-2-yl)carbonyl)piperazine

2. Alfamedin

3. Apo Doxazosin

4. Apo-doxazosin

5. Cardular

6. Cardura

7. Carduran

8. Carduran Neo

9. Ct, Doxazosin Von

10. Diblocin

11. Doxa Puren

12. Doxa-puren

13. Doxacor

14. Doxagamma

15. Doxamax

16. Doxatensa

17. Doxauro

18. Doxazomerck

19. Doxazosin

20. Doxazosin Al

21. Doxazosin Apogepha

22. Doxazosin Azu

23. Doxazosin Beta

24. Doxazosin Findusfit

25. Doxazosin Heumann

26. Doxazosin Klast

27. Doxazosin Monohydrochloride

28. Doxazosin Ratiopharm

29. Doxazosin Stada

30. Doxazosin Von Ct

31. Doxazosin Wolff

32. Doxazosin-ratiopharm

33. Doxazosin-wolff

34. Doxazosina Alter

35. Doxazosina Cinfa

36. Doxazosina Combino Pharm

37. Doxazosina Geminis

38. Doxazosina Normon

39. Doxazosina Pharmagenus

40. Doxazosina Ratiopharm

41. Doxazosina Ur

42. Gen Doxazosin

43. Gen-doxazosin

44. Jutalar

45. Mesylate, Doxazosin

46. Monohydrochloride, Doxazosin

47. Mtw Doxazosin

48. Mtw-doxazosin

49. Neo, Carduran

50. Novo Doxazosin

51. Novo-doxazosin

52. Progandol Neo

53. Ratio Doxazosin

54. Ratio-doxazosin

55. Ratiopharm, Doxazosina

56. Uk 33274

57. Uk-33274

58. Uk33274

59. Uriduct

60. Von Ct, Doxazosin

61. Zoxan

2.3.2 Depositor-Supplied Synonyms

1. 77883-43-3

2. Cardura

3. Carduran

4. Alfadil

5. Cardular

6. Cardura Xl

7. Doxazosin Mesilate

8. Cardenalin

9. Dedralen

10. Progandol

11. Tensiobas

12. Doxazosin (mesylate)

13. Uk 33274 Mesylate

14. Doxazosin (as Mesilate)

15. Doxazosin Methanesulfonate

16. (4-(4-amino-6,7-dimethoxyquinazolin-2-yl)piperazin-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-2-yl)methanone Methanesulfonate

17. Nsc-759284

18. 86p6pqk0mu

19. Mls000028455

20. Doxazomerck

21. Diblocin

22. Uk-33,274-27

23. Doxazosin Azu

24. Prostadilat

25. Cardoral

26. Cardoxan

27. Doksura

28. Doxaben

29. Doxolbran

30. Kaltensif

31. Normathen

32. Smr000058441

33. Supressin

34. Tonocardin

35. Benur

36. Cardular Uro

37. Diblocin Uro

38. Cardular Pp

39. Diblocin Pp

40. Uk-33274-27

41. Dsstox_cid_25598

42. Dsstox_rid_80991

43. Dsstox_gsid_45598

44. Piperazine, 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-((2,3-dihydro-1,4-benzodioxin-2-yl)carbonyl)-, Monomethanesulfonate

45. Uk 33274

46. Doxazocine

47. Duracin

48. Dosin

49. 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl)piperazine Monomethanesulfonate

50. Carduran Neo

51. Chebi:4709

52. Doxazosin Mesylate [usan]

53. [4-(4-amino-6,7-dimethoxyquinazolin-2-yl)piperazin-1-yl]-(2,3-dihydro-1,4-benzodioxin-3-yl)methanone;methanesulfonic Acid

54. 2-{4-[(2,3-dihydro-1,4-benzodioxin-2-yl)carbonyl]piperazin-1-yl}-6,7-dimethoxyquinazolin-4-amine; Methanesulfonic Acid

55. Hsdb 7082

56. Sr-01000003045

57. Unii-86p6pqk0mu

58. Doxazosin Mesylate [usan:usp]

59. Uk 33,274-27

60. Ncgc00017136-01

61. Cardura (tn)

62. Cas-77883-43-3

63. Mfcd00216023

64. Prestwick_1026

65. Doxazosin Mesylate Salt

66. Doxazosin Mesylate,(s)

67. Opera_id_1881

68. Doxazosin Mesylate (usp)

69. Doxazosin Mesilate (jp17)

70. Schembl42621

71. 2-[4-(2,3-dihydro-1,4-benzodioxin-2-ylcarbonyl)piperazin-1-yl]-6,7-dimethoxyquinazolin-4-amine; Methanesulfonic Acid

72. Mls000120399

73. Mls001148153

74. Mls002222292

75. Mls006011977

76. Chembl1200561

77. Doxazosin Mesilate [jan]

78. Dtxsid5045598

79. Hy-b0098a

80. Doxazosin Mesylate [hsdb]

81. Doxazosin Mesylate [vandf]

82. Hms1570l17

83. Hms2093j14

84. Hms2097l17

85. Hms2230l18

86. Hms3261o10

87. Hms3372c03

88. Hms3654j15

89. Hms3714l17

90. Hms3884o09

91. Pharmakon1600-01505976

92. Doxazosin Mesilate [mart.]

93. Bcp12163

94. Doxazosin Mesilate [who-dd]

95. Doxazosin Mesylate [usp-rs]

96. Tox21_110796

97. Tox21_500474

98. Nsc759284

99. S1324

100. Akos015895371

101. Piperazin-1-yl)(2,3-dihydrobenzo[b]

102. Tox21_110796_1

103. Ac-6848

104. Ccg-213583

105. Cs-1830

106. Ks-1052

107. Lp00474

108. Nsc 759284

109. Doxazosin Mesylate [orange Book]

110. Doxazosin Mesilate [ep Monograph]

111. Doxazosin Mesylate [usp Impurity]

112. Ncgc00016146-02

113. Ncgc00018158-09

114. Ncgc00093884-01

115. Ncgc00261159-01

116. 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-[4-(1,4-benzodioxan-2-yl)carpiperazin-1-yl)]-6,7-dimethoxyquinazoline Mesylate

117. 2-[4-(2,3-dihydro-1,4-benzodioxine-2-carbonyl)piperazin-1-yl]-6,7-dimethoxyquinazolin-4-amine; Methanesulfonic Acid

118. Bd164387

119. Doxazosin Mesylate [usp Monograph]

120. [1,4]dioxin-2-yl)methanone Methanesulfonate

121. D4126

122. Doxazosin Mesylate, >=97% (hplc), Powder

123. Eu-0100474

124. Ft-0625592

125. Sw197099-3

126. En300-53021

127. 91d858

128. C76492

129. D 9815

130. D00608

131. A839262

132. Sr-01000003045-2

133. Sr-01000003045-4

134. Sr-01000003045-8

135. Q27106443

136. Z1259084903

137. Doxazosin Mesilate, European Pharmacopoeia (ep) Reference Standard

138. Doxazosin Mesylate, United States Pharmacopeia (usp) Reference Standard

139. (4-(4-amino-6,7-dimethoxyquinazolin-2-yl)piperazin-1-yl)(2,3-dihydrobenzo[b][1,4]dioxin-2-yl)methanonemethanesulfonate

140. 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl)piperazine Methanesulphonate

141. 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-[(1,4-benzodioxan-2-yl)carbonyl]piperazine Methanesulfonate

142. 2,3,4a,8a-tetrahydro-1,4-benzodioxin-3-yl-[4-(4-amino-6,7-dimethoxy-quinazolin-2-yl)piperazin-1-yl]methanone; Methanesulfonate;doxazosin Mesylate

143. 4-amino-2-[4-(1,4-benzodioxan-2-carbonyl)piperazin-1-yl]-6,7-dimethoxyquinazoline Methanesulfonate

144. Methanone, (4-(4-amino-6,7-dimethoxy-2-quinazolinyl)-1-piperazinyl)(2,3-dihydro-1,4-benzodioxin-2-yl)-, Methanesulfonate (1:1)

145. Piperazine, 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-((2,3-dihydro-1,4-benzodioxin-2-yl)carbonyl)-, Monomethanesulphonate

2.4 Create Date
2005-06-24
3 Chemical and Physical Properties
Molecular Weight 547.6 g/mol
Molecular Formula C24H29N5O8S
Hydrogen Bond Donor Count2
Hydrogen Bond Acceptor Count12
Rotatable Bond Count4
Exact Mass547.17368407 g/mol
Monoisotopic Mass547.17368407 g/mol
Topological Polar Surface Area175 Ų
Heavy Atom Count38
Formal Charge0
Complexity770
Isotope Atom Count0
Defined Atom Stereocenter Count0
Undefined Atom Stereocenter Count1
Defined Bond Stereocenter Count0
Undefined Bond Stereocenter Count0
Covalently Bonded Unit Count2
4 Drug and Medication Information
4.1 Drug Information
1 of 6  
Drug NameCardura
Drug LabelCARDURA (doxazosin mesylate) is a quinazoline compound that is a selective inhibitor of the alpha1 subtype of alpha-adrenergic receptors. The chemical name of doxazosin mesylate is 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcar...
Active IngredientDoxazosin mesylate
Dosage FormTablet
RouteOral
Strengtheq 4mg base; eq 2mg base; eq 1mg base; eq 8mg base
Market StatusPrescription
CompanyPfizer

2 of 6  
Drug NameCardura xl
Drug LabelCARDURA XL contains doxazosin mesylate which is a quinazoline compound with the chemical name 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl) piperazine methanesulfonate. The empirical formula for doxazosin mesylate is C23H2...
Active IngredientDoxazosin mesylate
Dosage FormTablet, extended release
RouteOral
Strengtheq 4mg base; eq 8mg base
Market StatusPrescription
CompanyPfizer

3 of 6  
Drug NameDoxazosin mesylate
PubMed HealthDoxazosin (By mouth)
Drug ClassesAntihypertensive, Benign Prostatic Hypertrophy Agent, Cardiovascular Agent
Drug LabelDoxazosin mesylate is a quinazoline compound that is a selective inhibitor of the alpha1 subtype of alpha adrenergic receptors. The chemical name of doxazosin mesylate is 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl) piper...
Active IngredientDoxazosin mesylate
Dosage FormTablet
RouteOral
Strengtheq 4mg base; eq 2mg base; eq 1mg base; eq 8mg base
Market StatusPrescription
CompanyTeva; Apotex; Accord Hlthcare; Pliva; Mylan; Dava Pharms

4 of 6  
Drug NameCardura
Drug LabelCARDURA (doxazosin mesylate) is a quinazoline compound that is a selective inhibitor of the alpha1 subtype of alpha-adrenergic receptors. The chemical name of doxazosin mesylate is 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcar...
Active IngredientDoxazosin mesylate
Dosage FormTablet
RouteOral
Strengtheq 4mg base; eq 2mg base; eq 1mg base; eq 8mg base
Market StatusPrescription
CompanyPfizer

5 of 6  
Drug NameCardura xl
Drug LabelCARDURA XL contains doxazosin mesylate which is a quinazoline compound with the chemical name 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl) piperazine methanesulfonate. The empirical formula for doxazosin mesylate is C23H2...
Active IngredientDoxazosin mesylate
Dosage FormTablet, extended release
RouteOral
Strengtheq 4mg base; eq 8mg base
Market StatusPrescription
CompanyPfizer

6 of 6  
Drug NameDoxazosin mesylate
PubMed HealthDoxazosin (By mouth)
Drug ClassesAntihypertensive, Benign Prostatic Hypertrophy Agent, Cardiovascular Agent
Drug LabelDoxazosin mesylate is a quinazoline compound that is a selective inhibitor of the alpha1 subtype of alpha adrenergic receptors. The chemical name of doxazosin mesylate is 1-(4-amino-6,7-dimethoxy-2-quinazolinyl)-4-(1,4-benzodioxan-2-ylcarbonyl) piper...
Active IngredientDoxazosin mesylate
Dosage FormTablet
RouteOral
Strengtheq 4mg base; eq 2mg base; eq 1mg base; eq 8mg base
Market StatusPrescription
CompanyTeva; Apotex; Accord Hlthcare; Pliva; Mylan; Dava Pharms

4.2 Therapeutic Uses

Doxazosin is indicated for the treatment of both the urinary outflow obstruction and the obstructive and irritative symptoms associated with benign prostatic hyperplasia (BPH). Obstructive symptoms are hesitation, intermittency, dribbling, weak urinary stream, and incomplete emptying of the bladder; while irritative symptoms include nocturia, daytime frequency, urgency, and burning. Doxaxosin may be used in nomotensive or hypertensive patients. In normotensive patients with BPH, doxazosin does not appear to significantly lower blood pressure. In hypertensive patients with BPH, both conditions are effectively treated with doxazosin. The long term effects of doxazosin on the incidence of acute urinary obstruction or other complications of BPH or on the need for surgery have not yet been determined. /Included in US product labeling/ /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


Doxazosin is indicated in the treatment of hypertension. /Included in US product labeling/ /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


Antihypertensive; in treatment of benign prostatic hypertrophy. /Salt not specified/

O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 604


Evaluation of atherosclerosis is important in the treatment of hypertension. To evaluate the preventive effects of a small amount of alpha-blockade, arterial and endothelial dysfunction were measured by noninvasive tests, i.e., pulse wave velocity, acceleration plethysmography and strain-gauge plethysmography, in patients with essential hypertension. Fifteen patients (65+/-3 years old) with essential hypertension (WHO stage I or II) were analyzed in this study. We performed noninvasive evaluations to measure aortic stiffness and endothelial dysfunction, in addition to measuring blood pressure, cholesterol profile, and levels of cells adhesion molecules and nitric oxide before and 6 and 12 months after the start of doxazosin treatment (1.0 mg/day). Blood pressure and heart rate did not significantly change during treatment. The pulse wave velocity index was significantly reduced both at 6 (7.72+/-0.23 m/s; p<0.05) and 12 (7.34+/-0.26 m/s; p<0.05) months after the start of treatment compared to the pretreatment level that at baseline. There was also a significant improvement in b/a after 12 months (-0.46+/-0.04; p<0.05) and in d/a after 6 months (-0.38+/-0.03; p<0.05) and 12 months (-0.39+/-0.03; p=0.05) compared to the pretreatment values. Moreover, reactive hyperemia evaluated by strain-gauge plethysmography after 6 months (1.34+/-0.11; p<0.05) and 12 months (1.49+/-0.16; p<0.05) was significantly improved compared to that before treatment, and NOx was significantly increased after 12 months (89.7+/-15.7 micromol/l; p<0.005). These data suggest that a low dose of doxazosin may play an important role in improving arterial stiffness and endothelial dysfunction without changing cardiac hemodynamics. /Salt not specified/

Komai N et al; Hypertens Res 25(1) : p.5-10 (2002)


For more Therapeutic Uses (Complete) data for DOXAZOSIN MESYLATE (18 total), please visit the HSDB record page.


4.3 Drug Warning

Adverse effects occurring most frequently during doxazosin mesylate therapy for hypertension include dizziness, headache, drowsiness, lack of energy (eg, lethargy, fatigue), nausea, edema, and rhinitis. In patients receiving the drug for benign prostatic hyperplasia (BPH), the most frequent adverse effects are dizziness, headache, fatigue, edema, dyspnea, abdominal pain, and diarrhea. The frequency of adverse effects in controlled clinical trails generally has been lower in patients receiving doxazosin for BPH than in those receiving the drug for hypertension; however, dosages employed for this condition also generally have been lower than those for hypertension. /Salt not specified/

McEvoy, G.K. (ed.). American Hospital Formulary Service- Drug Information 2002. Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2002 (Plus Supplements)., p. 1819


While adverse effects occur frequently in patients receiving the drug, most are mild to moderate in severity, and discontinuance of doxazosin secondary to adverse effects was required in only 7% of patients with hypertension during clinical trials. The principal reasons for discontinuance in patients with hypertension were postural effects in 2% of patients and edema, malaise/fatigue, and heart rate disturbance each in about 0.7% of patients. In controlled clinical trials in patients with hypertension, only dizziness (including postural effects), weight gain, somnolence, and malaise/fatigue occurred at rates significantly greater than those for placebo; postural effects and edema appeared to be dose related. Only dizziness, fatigue, hypotension, edema, and dyspnea occurred significantly more frequently with the drug than placebo in controlled clinical trials for BPH; dizziness and dyspnea appeared to be dose-related. /Salt not specified/

McEvoy, G.K. (ed.). American Hospital Formulary Service- Drug Information 2002. Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2002 (Plus Supplements)., p. 1819


Besides dizziness ..., headache is the most common adverse nervous system effect associated with doxazosin therapy, occurring in about 14 or 10% of patients receiving the drug for hypertension or benign prostatic hyperplasia (BPH), respectively. Somnolence occurs in 5 or 3% of such patients, respectively, and pain in 2% of patients. Nervousness occurs in about 2% of patients receiving doxazosin for hypertension, and insomnia and anxiety occur in 1.2 and 1.1%, respectively, of those receiving the drug for BPH; insomnia occurs in 1% of hypertensive patients. Adverse nervous system effects occurring in 0.5-1% of patients include paresthesia, kinetic disorders, ataxia, hypertonia, hypoesthesia, agitation, depression, and decreased libido. Paresis, tremor, twitching, confusion, migraine, paroniria, amnesia, emotional lability, impaired concentration, abnormal thinking, and depresonalization have been reported in less than 0.5% of patients, but a causal relationship to the drug has not been established. /Salt not specified/

McEvoy, G.K. (ed.). American Hospital Formulary Service- Drug Information 2002. Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2002 (Plus Supplements)., p. 1819


Nausea, diarrhea, and dry mouth are the most common adverse GI effects of doxazosin in hypertensive patients, occurring in 3, 2, and 2% of such patients, respectively, and abdominal pain, diarrhea, dyspepsia, nausea, and dry mouth are the most common in those with benign prostatic hyperplasia (BPH), occurring in 2.4, 2.3, 1.7, 1.5, and 1.4% of such patients, respectively; dyspepsia occurs in 1% of hypertensive patients. Constipation and flatulence occur in 1% of patients receiving the drug for hypertension. Increased appetite, anorexia, fecal incontinence, and gastroenteritis have been reported in less than 0.5% of hypertensive patients but not directly attributed to the drug. Vomiting has been reported during postmarketing experience with doxazosin. /Salt not specified/

McEvoy, G.K. (ed.). American Hospital Formulary Service- Drug Information 2002. Bethesda, MD: American Society of Health-System Pharmacists, Inc. 2002 (Plus Supplements)., p. 1820


For more Drug Warnings (Complete) data for DOXAZOSIN MESYLATE (12 total), please visit the HSDB record page.


5 Pharmacology and Biochemistry
5.1 MeSH Pharmacological Classification

Adrenergic alpha-1 Receptor Antagonists

Drugs that bind to and block the activation of ADRENERGIC ALPHA-1 RECEPTORS. (See all compounds classified as Adrenergic alpha-1 Receptor Antagonists.)


Antihypertensive Agents

Drugs used in the treatment of acute or chronic vascular HYPERTENSION regardless of pharmacological mechanism. Among the antihypertensive agents are DIURETICS; (especially DIURETICS, THIAZIDE); ADRENERGIC BETA-ANTAGONISTS; ADRENERGIC ALPHA-ANTAGONISTS; ANGIOTENSIN-CONVERTING ENZYME INHIBITORS; CALCIUM CHANNEL BLOCKERS; GANGLIONIC BLOCKERS; and VASODILATOR AGENTS. (See all compounds classified as Antihypertensive Agents.)


5.2 FDA Pharmacological Classification
5.2.1 Pharmacological Classes
alpha-Adrenergic Blocker [EPC]; Adrenergic alpha-Antagonists [MoA]
5.3 Absorption, Distribution and Excretion

Most doxazosin metabolites are eliminated in the feces. /Salt not specified/

Hardman, J.G., L.E. Limbird, P.B., A.G. Gilman. Goodman and Gilman's The Pharmacological Basis of Therapeutics. 10th ed. New York, NY: McGraw-Hill, 2001., p. 246


Well absorbed from gastrointestinal tract; bioavailability is about 65%. /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


Elimination: Fecal: Unchanged drug, about 5%; metabolites, 63 to 65%. Renal: 9%. /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


5.4 Metabolism/Metabolites

Metabolized extensively in the liver. Although several active and inactive metabolites have been identified (2-piperazinyl, 6' and 7'-hydroxy,6' and 7'-O-desmethyl, and 2-amino), there is no evidence that they are present in substantial amounts. /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


5.5 Biological Half-Life

The half-life of doxazosin is approximately 20 hours ... /Salt not specified/

Hardman, J.G., L.E. Limbird, P.B., A.G. Gilman. Goodman and Gilman's The Pharmacological Basis of Therapeutics. 10th ed. New York, NY: McGraw-Hill, 2001., p. 246


Elimination /half life/: 19 to 22 hours; does not appear to be significantly influenced by age or mild to moderate renal impairment. /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


5.6 Mechanism of Action

Selective alpha1-adrenergic blocker related to prazosin, q.v. /Salt not specified/

O'Neil, M.J. (ed.). The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. 13th Edition, Whitehouse Station, NJ: Merck and Co., Inc., 2001., p. 604


Blocks postsynaptic alpha 1 receptors and cause vasodilation /Salt not specified/

Ellenhorn, M.J., S. Schonwald, G. Ordog, J. Wasserberger. Ellenhorn's Medical Toxicology: Diagnosis and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams and Wilkins, 1997., p. 552


Hypertension: Blockade of alpha1-adrenergic receptors by doxazosin results in peripheral vasodilation, which produces a fall in blood pressure because of decreased peripheral vascular resistance. Benign prostatic hyperplasia: Relaxation of smooth muscle in the bladder neck, prostate, and prostate capsule produced by alpha1-adrenergic blockade results in a reduction in urethral resistance and pressure, bladder outlet resistance, and urinary symptoms. /Salt not specified/

MICROMEDEX Thomson Health Care. USPDI - Drug Information for the Health Care Professional. 22nd ed. Volume 1. MICROMEDEX Thomson Health Care, Greenwood Village, CO. 2002. Content Reviewed and Approved by the U.S. Pharmacopeial Convention, Inc., p. 1278


Previous studies have demonstrated that the alpha(1)-adrenergic receptor antagonist doxazosin (Dox) inhibits multiple mitogenic signaling pathways in human vascular smooth muscle cells. This broad antiproliferative activity of Dox occurs through a novel mechanism unrelated to its blocking the alpha(1)-adrenergic receptor. Flow cytometry demonstrated that Dox prevents mitogen-induced G(1)-->S progression of human coronary artery smooth muscle cells (CASMCs) in a dose-dependent manner, with a maximal reduction of S-phase transition by 88+/-10.5% in 20 ng/mL platelet-derived growth factor and 1 micromol/L insulin (P+I)-stimulated cells (P<0.01 for 10 micromol/L Dox versus P+I alone) and 52+/-18.7% for 10% FBS-induced mitogenesis (P<0.05 for 10 micromol/L Dox versus 10% FBS alone). Inhibition of G(1) exit by Dox was accompanied by a significant blockade of retinoblastoma protein (Rb) phospstimulated quiescent CASMCs to progress through G(1) and enter the S phase. E2F-mediated G(1) exit was not affected by Dox, suggesting that it targets events upstream from Rb hyperphosphorylation. Downregulation of the cyclin-dependent kinase inhibitory protein p27 is important for maximal activation of G(1) cyclin/cyclin-dependent kinase holoenzymes to overcome the cell cycle inhibitory activity of Rb. In Western blot analysis, p27 levels decreased after mitogenic stimulation (after P+I, 43+/-1.8% of quiescent cells [P<0.01 versus quiescent cells]; after 10% FBS, 55+/-7.7% of quiescent cells [P<0. 05 versus quiescent cells]), whereas the addition of Dox (10 micromol/L) markedly attenuated its downregulation (after P+I, 90+/-8.3% of quiescent cells [P<0.05 versus P+I alone]; after 10% FBS, 78+/-8.3% of quiescent cells [P<0.05 versus 10% FBS alone]). Furthermore, Dox inhibited cyclin A expression, an E2F regulated gene that is essential for cell cycle progression into the S phase. The present study demonstrates that Dox inhibits CASMC proliferation by blocking cell cycle progression from the G(0)/G(1) phase to the S phase. This G(1)-->S blockade likely results from an inhibition of mitogen-induced Rb hyperphosphorylation through prevention of p27 downregulation. /Salt not specified/

Kintscher U et al; Arterioscler Thromb Vasc Biol 20(5): p.1216-1224 (2002)


For more Mechanism of Action (Complete) data for DOXAZOSIN MESYLATE (6 total), please visit the HSDB record page.