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Micronutrient Information Center

References: Garlic and Organosulfur Compounds


1. Lawson LD. Garlic: a review of its medicinal effects and indicated active compounds. In: Lawson LD, Bauer R, eds. Phytomedicines of Europe: Chemistry and Biological Activity. Washington, D. C.: American Chemical Society; 1998:177-209.

2. Block E. The chemistry of garlic and onions. Sci Am. 1985;252(3):114-119. (PubMed)

3. Blumenthal M. Herb Sales Down 7.4 Percent in Mainstream Market. HerbalGram: American Botanical Council; 2005:63.

4. Tapiero H, Townsend DM, Tew KD. Organosulfur compounds from alliaceae in the prevention of human pathologies. Biomed Pharmacother. 2004;58(3):183-193. (PubMed)

5. Lawson LD, Wang ZJ. Allicin and allicin-derived garlic compounds increase breath acetone through allyl methyl sulfide: use in measuring allicin bioavailability. J Agric Food Chem. 2005;53(6):1974-1983. (PubMed)

6. Germain E, Auger J, Ginies C, Siess MH, Teyssier C. In vivo metabolism of diallyl disulphide in the rat: identification of two new metabolites. Xenobiotica. 2002;32(12):1127-1138. (PubMed)

7. Lachmann G, Lorenz D, Radeck W, Steiper M. [The pharmacokinetics of the S35 labeled labeled garlic constituents alliin, allicin and vinyldithiine]. Arzneimittelforschung. 1994;44(6):734-743. (PubMed)

8. de Rooij BM, Boogaard PJ, Rijksen DA, Commandeur JN, Vermeulen NP. Urinary excretion of N-acetyl-S-allyl-L-cysteine upon garlic consumption by human volunteers. Arch Toxicol. 1996;70(10):635-639. (PubMed)

9. Jandke J, Spiteller G. Unusual conjugates in biological profiles originating from consumption of onions and garlic. J Chromatogr. 1987;421(1):1-8. (PubMed)

10. Kodera Y, Suzuki A, Imada O, et al. Physical, chemical, and biological properties of s-allylcysteine, an amino acid derived from garlic. J Agric Food Chem. 2002;50(3):622-632. (PubMed)

11. Steiner M, Li W. Aged garlic extract, a modulator of cardiovascular risk factors: a dose-finding study on the effects of AGE on platelet functions. J Nutr. 2001;131(3s):980S-984S. (PubMed)

12. Gebhardt R, Beck H. Differential inhibitory effects of garlic-derived organosulfur compounds on cholesterol biosynthesis in primary rat hepatocyte cultures. Lipids. 1996;31(12):1269-1276. (PubMed)

13. Ferri N, Yokoyama K, Sadilek M, et al. Ajoene, a garlic compound, inhibits protein prenylation and arterial smooth muscle cell proliferation. Br J Pharmacol. 2003;138(5):811-818. (PubMed)

14. Liu L, Yeh YY. S-alk(en)yl cysteines of garlic inhibit cholesterol synthesis by deactivating HMG-CoA reductase in cultured rat hepatocytes. J Nutr. 2002;132(6):1129-1134. (PubMed)

15. Chan KC, Hsu CC, Yin MC. Protective effect of three diallyl sulphides against glucose-induced erythrocyte and platelet oxidation, and ADP-induced platelet aggregation. Thromb Res. 2002;108(5-6):317-322. (PubMed)

16. Lawson LD, Ransom DK, Hughes BG. Inhibition of whole blood platelet-aggregation by compounds in garlic clove extracts and commercial garlic products. Thromb Res. 1992;65(2):141-156. (PubMed)

17. Blake GJ, Ridker PM. C-reactive protein and other inflammatory risk markers in acute coronary syndromes. J Am Coll Cardiol. 2003;41(4 Suppl S):37S-42S. (PubMed)

18. Ali M, Thomson M, Afzal M. Garlic and onions: their effect on eicosanoid metabolism and its clinical relevance. Prostaglandins Leukot Essent Fatty Acids. 2000;62(2):55-73. (PubMed)

19. Dirsch VM, Kiemer AK, Wagner H, Vollmar AM. Effect of allicin and ajoene, two compounds of garlic, on inducible nitric oxide synthase. Atherosclerosis. 1998;139(2):333-339. (PubMed)

20. Kim KM, Chun SB, Koo MS, et al. Differential regulation of NO availability from macrophages and endothelial cells by the garlic component S-allyl cysteine. Free Radic Biol Med. 2001;30(7):747-756. (PubMed)

21. Chang HP, Huang SY, Chen YH. Modulation of cytokine secretion by garlic oil derivatives is associated with suppressed nitric oxide production in stimulated macrophages. J Agric Food Chem. 2005;53(7):2530-2534. (PubMed)

22. Keiss HP, Dirsch VM, Hartung T, et al. Garlic (Allium sativum L.) modulates cytokine expression in lipopolysaccharide-activated human blood thereby inhibiting NF-kappaB activity. J Nutr. 2003;133(7):2171-2175. (PubMed)

23. Hedin U, Roy J, Tran PK. Control of smooth muscle cell proliferation in vascular disease. Curr Opin Lipidol. 2004;15(5):559-565. (PubMed)

24. Campbell JH, Efendy JL, Smith NJ, Campbell GR. Molecular basis by which garlic suppresses atherosclerosis. J Nutr. 2001;131(3s):1006S-1009S. (PubMed)

25. Golovchenko I, Yang CH, Goalstone ML, Draznin B. Garlic extract methylallyl thiosulfinate blocks insulin potentiation of platelet-derived growth factor-stimulated migration of vascular smooth muscle cells. Metabolism. 2003;52(2):254-259. (PubMed)

26. Banerjee SK, Mukherjee PK, Maulik SK. Garlic as an antioxidant: the good, the bad and the ugly. Phytother Res. 2003;17(2):97-106. (PubMed)

27. Dhawan V, Jain S. Effect of garlic supplementation on oxidized low density lipoproteins and lipid peroxidation in patients of essential hypertension. Mol Cell Biochem. 2004;266(1-2):109-115. (PubMed)

28. Yang CS, Chhabra SK, Hong JY, Smith TJ. Mechanisms of inhibition of chemical toxicity and carcinogenesis by diallyl sulfide (DAS) and related compounds from garlic. J Nutr. 2001;131(3s):1041S-1045S. (PubMed)

29. Brady JF, Ishizaki H, Fukuto JM, et al. Inhibition of cytochrome P-450 2E1 by diallyl sulfide and its metabolites. Chem Res Toxicol. 1991;4(6):642-647. (PubMed)

30. Jeong HG, Lee YW. Protective effects of diallyl sulfide on N-nitrosodimethylamine-induced immunosuppression in mice. Cancer Lett. 1998;134(1):73-79. (PubMed)

31. Park KA, Kweon S, Choi H. Anticarcinogenic effect and modification of cytochrome P450 2E1 by dietary garlic powder in diethylnitrosamine-initiated rat hepatocarcinogenesis. J Biochem Mol Biol. 2002;35(6):615-622. (PubMed)

32. Gurley BJ, Gardner SF, Hubbard MA, et al. Cytochrome P450 phenotypic ratios for predicting herb-drug interactions in humans. Clin Pharmacol Ther. 2002;72(3):276-287. (PubMed)

33. Loizou GD, Cocker J. The effects of alcohol and diallyl sulphide on CYP2E1 activity in humans: a phenotyping study using chlorzoxazone. Hum Exp Toxicol. 2001;20(7):321-327. (PubMed)

34. Munday R, Munday CM. Induction of phase II enzymes by aliphatic sulfides derived from garlic and onions: an overview. Methods Enzymol. 2004;382:449-456. (PubMed)

35. Andorfer JH, Tchaikovskaya T, Listowsky I. Selective expression of glutathione S-transferase genes in the murine gastrointestinal tract in response to dietary organosulfur compounds. Carcinogenesis. 2004;25(3):359-367. (PubMed)

36. Hatono S, Jimenez A, Wargovich MJ. Chemopreventive effect of S-allylcysteine and its relationship to the detoxification enzyme glutathione S-transferase. Carcinogenesis. 1996;17(5):1041-1044. (PubMed)

37. Munday R, Munday CM. Relative activities of organosulfur compounds derived from onions and garlic in increasing tissue activities of quinone reductase and glutathione transferase in rat tissues. Nutr Cancer. 2001;40(2):205-210. (PubMed)

38. Chen C, Pung D, Leong V, et al. Induction of detoxifying enzymes by garlic organosulfur compounds through transcription factor Nrf2: effect of chemical structure and stress signals. Free Radic Biol Med. 2004;37(10):1578-1590. (PubMed)

39. Munday R, Munday CM. Low doses of diallyl disulfide, a compound derived from garlic, increase tissue activities of quinone reductase and glutathione transferase in the gastrointestinal tract of the rat. Nutr Cancer. 1999;34(1):42-48. (PubMed)

40. Kweon S, Park KA, Choi H. Chemopreventive effect of garlic powder diet in diethylnitrosamine-induced rat hepatocarcinogenesis. Life Sci. 2003;73(19):2515-2526. (PubMed)

41. Stewart ZA, Westfall MD, Pietenpol JA. Cell-cycle dysregulation and anticancer therapy. Trends Pharmacol Sci. 2003;24(3):139-145. (PubMed)

42. Herman-Antosiewicz A, Singh SV. Signal transduction pathways leading to cell cycle arrest and apoptosis induction in cancer cells by Allium vegetable-derived organosulfur compounds: a review. Mutat Res. 2004;555(1-2):121-131. (PubMed)

43. Knowles LM, Milner JA. Possible mechanism by which allyl sulfides suppress neoplastic cell proliferation. J Nutr. 2001;131(3s):1061S-1066S. (PubMed)

44. Wu X, Kassie F, Mersch-Sundermann V. Induction of apoptosis in tumor cells by naturally occurring sulfur-containing compounds. Mutat Res. 2005;589(2):81-102. (PubMed)

45. Balasenthil S, Rao KS, Nagini S. Apoptosis induction by S-allylcysteine, a garlic constituent, during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis. Cell Biochem Funct. 2002;20(3):263-268. (PubMed)

46. Balasenthil S, Rao KS, Nagini S. Garlic induces apoptosis during 7,12-dimethylbenz[a]anthracene-induced hamster buccal pouch carcinogenesis. Oral Oncol. 2002;38(5):431-436. (PubMed)

47. Fenwick GR, Hanley AB. The genus Allium--Part 3. Crit Rev Food Sci Nutr. 1985;23(1):1-73. (PubMed)

48. Harris JC, Cottrell SL, Plummer S, Lloyd D. Antimicrobial properties of Allium sativum (garlic). Appl Microbiol Biotechnol. 2001;57(3):282-286. (PubMed)

49. Ankri S, Mirelman D. Antimicrobial properties of allicin from garlic. Microbes Infect. 1999;1(2):125-129. (PubMed)

50. Cavallito CJ, Bailey JH. Allicin, the antibacterial principle of Allium sativum. I. Isolation, physical properties and antibacterial action. J Am Chem Soc. 1944;66(11):1950-1951.

51.Martin KW, Ernst E. Herbal medicines for treatment of bacterial infections: a review of controlled clinical trials. J Antimicrob Chemother. 2003;51(2):241-246. (PubMed)

52. Ledezma E, Marcano K, Jorquera A, et al. Efficacy of ajoene in the treatment of tinea pedis: a double-blind and comparative study with terbinafine. J Am Acad Dermatol. 2000;43(5 Pt 1):829-832. (PubMed)

53. Keys A. Wine, garlic, and CHD in seven countries. Lancet. 1980;1(8160):145-146. (PubMed)

54. Ackermann RT, Mulrow CD, Ramirez G, Gardner CD, Morbidoni L, Lawrence VA. Garlic shows promise for improving some cardiovascular risk factors. Arch Intern Med. 2001;161(6):813-824. (PubMed)

55. Alder R, Lookinland S, Berry JA, Williams M. A systematic review of the effectiveness of garlic as an anti-hyperlipidemic agent. J Am Acad Nurse Pract. 2003;15(3):120-129. (PubMed)

56. Stevinson C, Pittler MH, Ernst E. Garlic for treating hypercholesterolemia. A meta-analysis of randomized clinical trials. Ann Intern Med. 2000;133(6):420-429. (PubMed)

57. Berthold HK, Sudhop T, von Bergmann K. Effect of a garlic oil preparation on serum lipoproteins and cholesterol metabolism: a randomized controlled trial. JAMA. 1998;279(23):1900-1902. (PubMed)

58. Gardner CD, Chatterjee LM, Carlson JJ. The effect of a garlic preparation on plasma lipid levels in moderately hypercholesterolemic adults. Atherosclerosis. 2001;154(1):213-220. (PubMed)

59. Kannar D, Wattanapenpaiboon N, Savige GS, Wahlqvist ML. Hypocholesterolemic effect of an enteric-coated garlic supplement. J Am Coll Nutr. 2001;20(3):225-231. (PubMed)

60. McCrindle BW, Helden E, Conner WT. Garlic extract therapy in children with hypercholesterolemia. Arch Pediatr Adolesc Med. 1998;152(11):1089-1094. (PubMed)

61. Neil HA, Silagy CA, Lancaster T, et al. Garlic powder in the treatment of moderate hyperlipidaemia: a controlled trial and meta-analysis. J R Coll Physicians Lond. 1996;30(4):329-334. (PubMed)

62. Turner B, Molgaard C, Marckmann P. Effect of garlic (Allium sativum) powder tablets on serum lipids, blood pressure and arterial stiffness in normo-lipidaemic volunteers: a randomised, double-blind, placebo-controlled trial. Br J Nutr. 2004;92(4):701-706. (PubMed)

63. Lawson LD, Wang ZJ, Papadimitriou D. Allicin release under simulated gastrointestinal conditions from garlic powder tablets employed in clinical trials on serum cholesterol. Planta Med. 2001;67(1):13-18. (PubMed)

64. Rahman K, Billington D. Dietary supplementation with aged garlic extract inhibits ADP-induced platelet aggregation in humans. J Nutr. 2000;130(11):2662-2665. (PubMed)

65. Brace LD. Cardiovascular benefits of garlic (Allium sativum L). J Cardiovasc Nurs. 2002;16(4):33-49. (PubMed)

66. Adler AJ, Holub BJ. Effect of garlic and fish-oil supplementation on serum lipid and lipoprotein concentrations in hypercholesterolemic men. Am J Clin Nutr. 1997;65(2):445-450. (PubMed)

67. Auer W, Eiber A, Hertkorn E, et al. Hypertension and hyperlipidaemia: garlic helps in mild cases. Br J Clin Pract Suppl. 1990;69:3-6. (PubMed)

68. Vorberg G, Schneider B. Therapy with garlic: results of a placebo-controlled, double-blind study. Br J Clin Pract Suppl. 1990;69:7-11. (PubMed)

69. Koscielny J, Klussendorf D, Latza R, et al. The antiatherosclerotic effect of Allium sativum. Atherosclerosis. 1999;144(1):237-249. (PubMed)

70. Siegel G, Klussendorf D. The anti-atheroslerotic effect of Allium sativum: statistics re-evaluated. Atherosclerosis. 2000;150(2):437-438. (PubMed)

71. Budoff MJ, Takasu J, Flores FR, et al. Inhibiting progression of coronary calcification using Aged Garlic Extract in patients receiving statin therapy: a preliminary study. Prev Med. 2004;39(5):985-991. (PubMed)

72. Vliegenthart R. Non-invasive assessment of coronary calcification. Eur J Epidemiol. 2004;19(12):1063-1072. (PubMed)

73. Takezaki T, Gao CM, Ding JH, Liu TK, Li MS, Tajima K. Comparative study of lifestyles of residents in high and low risk areas for gastric cancer in Jiangsu Province, China; with special reference to allium vegetables. J Epidemiol. 1999;9(5):297-305. (PubMed)

74. Buiatti E, Palli D, Decarli A, et al. A case-control study of gastric cancer and diet in Italy. Int J Cancer. 1989;44(4):611-616. (PubMed)

75. Kim HJ, Chang WK, Kim MK, Lee SS, Choi BY. Dietary factors and gastric cancer in Korea: a case-control study. Int J Cancer. 2002;97(4):531-535. (PubMed)

76. You WC, Blot WJ, Chang YS, et al. Allium vegetables and reduced risk of stomach cancer. J Natl Cancer Inst. 1989;81(2):162-164. (PubMed)

77. Dorant E, van den Brandt PA, Goldbohm RA, Sturmans F. Consumption of onions and a reduced risk of stomach carcinoma. Gastroenterology. 1996;110(1):12-20. (PubMed)

78. Fleischauer AT, Poole C, Arab L. Garlic consumption and cancer prevention: meta-analyses of colorectal and stomach cancers. Am J Clin Nutr. 2000;72(4):1047-1052. (PubMed)

79. Canizares P, Gracia I, Gomez LA, et al. Allyl-thiosulfinates, the bacteriostatic compounds of garlic against Helicobacter pylori. Biotechnol Prog. 2004;20(1):397-401. (PubMed)

80. O'Gara EA, Hill DJ, Maslin DJ. Activities of garlic oil, garlic powder, and their diallyl constituents against Helicobacter pylori. Appl Environ Microbiol. 2000;66(5):2269-2273. (PubMed)

81. Salih BA, Abasiyanik FM. Does regular garlic intake affect the prevalence of Helicobacter pylori in asymptomatic subjects? Saudi Med J. 2003;24(8):842-845. (PubMed)

82. You WC, Zhang L, Gail MH, et al. Helicobacter pylori infection, garlic intake and precancerous lesions in a Chinese population at low risk of gastric cancer. Int J Epidemiol. 1998;27(6):941-944. (PubMed)

83. Graham DY, Anderson SY, Lang T. Garlic or jalapeno peppers for treatment of Helicobacter pylori infection. Am J Gastroenterol. 1999;94(5):1200-1202. (PubMed)

84. McNulty CA, Wilson MP, Havinga W, Johnston B, O'Gara EA, Maslin DJ. A pilot study to determine the effectiveness of garlic oil capsules in the treatment of dyspeptic patients with Helicobacter pylori. Helicobacter. 2001;6(3):249-253. (PubMed)

85. Aydin A, Ersoz G, Tekesin O, Akcicek E, Tuncyurek M. Garlic oil and Helicobacter pylori infection. Am J Gastroenterol. 2000;95(2):563-564. (PubMed)

86. Ernst E. Is garlic an effective treatment for Helicobacter pylori infection? Arch Intern Med. 1999;159(20):2484-2485. (PubMed)

87. Hu JF, Liu YY, Yu YK, Zhao TZ, Liu SD, Wang QQ. Diet and cancer of the colon and rectum: a case-control study in China. Int J Epidemiol. 1991;20(2):362-367. (PubMed)

88. Iscovich JM, L'Abbe KA, Castelleto R, et al. Colon cancer in Argentina. I: Risk from intake of dietary items. Int J Cancer. 1992;51(6):851-857. (PubMed)

89. Levi F, Pasche C, La Vecchia C, Lucchini F, Franceschi S. Food groups and colorectal cancer risk. Br J Cancer. 1999;79(7-8):1283-1287. (PubMed)

90. Dorant E, van den Brandt PA, Goldbohm RA. A prospective cohort study on the relationship between onion and leek consumption, garlic supplement use and the risk of colorectal carcinoma in The Netherlands. Carcinogenesis. 1996;17(3):477-484. (PubMed)

91. Giovannucci E, Rimm EB, Stampfer MJ, Colditz GA, Ascherio A, Willett WC. Intake of fat, meat, and fiber in relation to risk of colon cancer in men. Cancer Res. 1994;54(9):2390-2397. (PubMed)

92. Steinmetz KA, Kushi LH, Bostick RM, Folsom AR, Potter JD. Vegetables, fruit, and colon cancer in the Iowa Women's Health Study. Am J Epidemiol. 1994;139(1):1-15. (PubMed)

93. Witte JS, Longnecker MP, Bird CL, Lee ER, Frankl HD, Haile RW. Relation of vegetable, fruit, and grain consumption to colorectal adenomatous polyps. Am J Epidemiol. 1996;144(11):1015-1025. (PubMed)

94. Tanaka S, Haruma K, Kunihiro M, et al. Effects of aged garlic extract (AGE) on colorectal adenomas: a double-blinded study. Hiroshima J Med Sci. 2004;53(3-4):39-45. (PubMed)

95. Bianchini F, Vainio H. Allium vegetables and organosulfur compounds: do they help prevent cancer? Environ Health Perspect. 2001;109(9):893-902. (PubMed)

96. Song K, Milner JA. The influence of heating on the anticancer properties of garlic. J Nutr. 2001;131(3s):1054S-1057S. (PubMed)

97. Song K, Milner JA. Heating garlic inhibits its ability to suppress 7, 12-dimethylbenz(a)anthracene-induced DNA adduct formation in rat mammary tissue. J Nutr. 1999;129(3):657-661. (PubMed)

98. Staba EJ, Lash L, Staba JE. A commentary on the effects of garlic extraction and formulation on product composition. J Nutr. 2001;131(3s):1118S-1119S. (PubMed)

99. Dietary Supplements: Garlic. The United States Pharmacopeia. Vol 28. Rockville, MD: United States Pharmacopeial Convention, Inc.; 2005:2087-2092.

100. Lawson LD, Wang ZJ. Low allicin release from garlic supplements: a major problem due to the sensitivities of alliinase activity. J Agric Food Chem. 2001;49(5):2592-2599. (PubMed)

101. Amagase H, Petesch BL, Matsuura H, Kasuga S, Itakura Y. Intake of garlic and its bioactive components. J Nutr. 2001;131(3s):955S-962S. (PubMed)

102. Steiner M, Khan AH, Holbert D, Lin RI. A double-blind crossover study in moderately hypercholesterolemic men that compared the effect of aged garlic extract and placebo administration on blood lipids. Am J Clin Nutr. 1996;64(6):866-870. (PubMed)

103. Mulrow C, Lawrence V, Ackermann R, et al. Garlic: effects on cardiovascular risks and disease, protective effects against cancer, and clinical adverse effects. Agency for Healthcare Research and Quality [Evidence Report/Technology Assessment No. 20]. October, 2000. Available at: http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=hstat1.chapter.28361. Accessed April 10, 2004.

104. Burnham BE. Garlic as a possible risk for postoperative bleeding. Plast Reconstr Surg. 1995;95(1):213. (PubMed)

105. Carden SM, Good WV, Carden PA, Good RM. Garlic and the strabismus surgeon. Clin Experiment Ophthalmol. 2002;30(4):303-304. (PubMed)

106. German K, Kumar U, Blackford HN. Garlic and the risk of TURP bleeding. Br J Urol. 1995;76(4):518. (PubMed)

107. Rose KD, Croissant PD, Parliament CF, Levin MB. Spontaneous spinal epidural hematoma with associated platelet dysfunction from excessive garlic ingestion: a case report. Neurosurgery. 1990;26(5):880-882. (PubMed)

108. Anibarro B, Fontela JL, De La Hoz F. Occupational asthma induced by garlic dust. J Allergy Clin Immunol. 1997;100(6 Pt 1):734-738. (PubMed)

109. Jappe U, Bonnekoh B, Hausen BM, Gollnick H. Garlic-related dermatoses: case report and review of the literature. Am J Contact Dermat. 1999;10(1):37-39. (PubMed)

110. Ziaei S, Hantoshzadeh S, Rezasoltani P, Lamyian M. The effect of garlic tablet on plasma lipids and platelet aggregation in nulliparous pregnants at high risk of preeclampsia. Eur J Obstet Gynecol Reprod Biol. 2001;99(2):201-206. (PubMed)

111. Mennella JA, Beauchamp GK. Maternal diet alters the sensory qualities of human milk and the nursling's behavior. Pediatrics. 1991;88(4):737-744. (PubMed)

112. Sunter WH. Warfarin and garlic. Pharm J. 1991;246:722.

113. Izzo AA, Ernst E. Interactions between herbal medicines and prescribed drugs: a systematic review. Drugs. 2001;61(15):2163-2175. (PubMed)

114.  Piscitelli SC, Burstein AH, Welden N, Gallicano KD, Falloon J. The effect of garlic supplements on the pharmacokinetics of saquinavir. Clin Infect Dis. 2002;34(2):234-238. (PubMed)

115. Markowitz JS, Devane CL, Chavin KD, Taylor RM, Ruan Y, Donovan JL. Effects of garlic (Allium sativum L.) supplementation on cytochrome P450 2D6 and 3A4 activity in healthy volunteers. Clin Pharmacol Ther. 2003;74(2):170-177. (PubMed)

116. Gallicano K, Foster B, Choudhri S. Effect of short-term administration of garlic supplements on single-dose ritonavir pharmacokinetics in healthy volunteers. Br J Clin Pharmacol. 2003;55(2):199-202. (PubMed)