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Drug Interactions: Human

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Can cranberry extract and vitamin C + Zn supplements affect the in vivo activity of paraoxonase 1, antioxidant potential, and lipid status?.

Posted: 
February 15, 2014
Authors: 
Begcevic I, Simundic AM, Nikolac N, Dobrijevic S, Rajkovic MG, Tesija-Kuna A
Journal: 
Clin Lab 59(9-10):1053-60
Abstract: 

BACKGROUND: The modern way of life exposes us to substantial oxidative stress, putting the focus on the research of antioxidant effects of dietary supplements. Recent studies have shown that the effectiveness of particular vitamins and herbal preparations might have an effect on paraoxonase activity. Paraoxonase 1 is an HDL associated enzyme which prevents the oxidation of LDL. Several studies have shown the beneficial effect of some dietary components to the activity of paraoxonase. The aim of this study was to analyze the effects of cranberry extract and vitamin C and zinc preparations (vitamin C + Zn) on serum paraoxonase 1 activity, antioxidant status, and glucose and lipid concentration.

METHODS: The study included 31 healthy volunteers (median age 24 years). They were divided into 3 groups according to the intervention type and smoking status and exposed to commercially available preparations of the cranberry extract (2 g/day) and vitamin C + Zn (300 mg/day) during 4 weeks.

RESULTS: The results have shown that there is a significant increase in the activity of the paraoxonase 1 in nonsmokers after the intervention with the cranberry extract as well as with vitamin C + Zn preparations. Also, total antioxidant status increased in the non-smokers subgroup after intervention with vitamin C + Zn. However, the lipid profile did not change significantly in response to antioxidant preparations.

CONCLUSIONS: Our results show that antioxidant supplements can increase the antioxidant potential of an organism as well as paraoxonase 1 activity. This observation is pointing to the potential complementary role of dietary supplements in the primary prevention of atherosclerosis.

Warfarin-cranberry juice interaction.

Posted: 
January 26, 2012
Authors: 
Hamann GL, Campbell JD, George CM
Journal: 
Ann Pharmacother. 45(3):e17
Abstract: 

OBJECTIVE: To report a case of warfarin-cranberry juice interaction, which resulted in an international normalized ratio (INR) elevation on 2 separate occasions.
CASE SUMMARY: A 46-year-old female was receiving a total weekly dose of 56 mg of warfarin. During the 4 months prior to the incident INR, her average INR was 2.0, with a range of 1.6-2.2, while taking the same weekly dose of warfarin. Her INR increased to 4.6 after drinking approximately 1.5 quarts (1420 mL) of cranberry juice cocktail daily for 2 days. Her INR 14 days later without cranberry juice cocktail consumption was 2.3. For the next 3 months, while taking warfarin 56 mg per week, her average INR was 2.1, with a range of 1.4-2.5. At a subsequent visit, after drinking approximately 2 quarts (1893 mL) of cranberry juice cocktail daily for 3-4 days, her INR had increased to 6.5. Her INR after holding warfarin for 3 days was 1.86. Her INR 7 days after resuming the weekly dose of warfarin 56 mg was 3.2. During both of the elevated INR episodes, no other factors were identified that would have resulted in an elevated INR, such as drug, herbal, disease, or other food interactions. An objective causality assessment revealed the interaction was highly probable.
DISCUSSION: Warfarin is the most commonly used anticoagulant for chronic therapy. There have been several case reports of cranberry juice or cranberry sauce potentiating the effects of warfarin by elevating the INR; however, clinical trials evaluating this interaction have failed to demonstrate a significant effect on an INR.
CONCLUSIONS: Our case report describes INR elevations in a patient previously stable on warfarin after ingestion of cranberry juice cocktail daily for several days. This elevation occurred on 2 separate occasions, which distinguishes our case from other published literature.

Pharmacodynamic interaction of warfarin with cranberry but not with garlic in healthy subjects1

Posted: 
December 17, 2010
Authors: 
Abdul MJM, Jiang X, Williams KM, Day RO, Roufogalis BD, Liauw WS, Xu H, McLachlan AJ.
Journal: 
Br J Pharmacol 154(8):1691-1700
Abstract: 

Background and purpose: Patients commonly take complementary medicines in conjunction with warfarin yet evidence supporting the safety or the risk of a herb–drug interaction is lacking. The aim of this study was to investigate the possible impact of two commonly used herbal medicines, garlic and cranberry, on the pharmacokinetics and pharmacodynamics of warfarin in healthy male subjects. Experimental approach: An open-label, three-treatment, randomized crossover clinical trial was undertaken and involved 12 healthy male subjects of known CYP2C9 and VKORC1 genotype. A single dose of 25mg warfarin was administered alone or after 2 weeks of pretreatment with either garlic or cranberry. Warfarin enantiomer concentrations, INR, platelet aggregation and clotting factor activity were measured to assess pharmacokinetic and pharmacodynamic interactions between warfarin and herbal medicines. Key results: Cranberry significantly increased the area under the INR–time curve by 30% when administered with warfarin compared with treatment with warfarin alone. Cranberry did not alter S- or R-warfarin pharmacokinetics or plasma protein binding. Co-administration of garlic did not significantly alter warfarin pharmacokinetics or pharmacodynamics. Both herbal medicines showed some evidence of VKORC1 (not CYP2C9) genotype-dependent interactions with warfarin, which is worthy of further investigation.Conclusions and implications: Cranberry alters the pharmacodynamics of warfarin with the potential to increase its effectssignificantly. Co-administration of warfarin and cranberry requires careful monitoring.

Effect of hypochlorhydria due to omeprazole treatment or atrophic gastritis on protein-bound vitamin B12 absorption.

Posted: 
November 13, 2010
Authors: 
Saltzman JR, Kemp JA, Golner BB, Pedrosa MC, Dallal GE, Russell RM
Journal: 
J Am Coll Nutr 13(6):584-91
Abstract: 

OBJECTIVE: To investigate the effects of hypochlorhydria and acidic drink ingestion on protein-bound vitamin B12 absorption in elderly subjects.

METHODS: Absorption of protein-bound vitamin B12 was examined in elderly normal subjects (n = 8), and in hypochlorhydric subjects due to omeprazole treatment (n = 8) or with atrophic gastritis (n = 3). Subjects underwent absorption tests of protein-bound vitamin B12 ingested with water, cranberry juice and 0.1 N hydrochloric acid.

RESULTS: Protein-bound vitamin B12 absorption was lower in the omeprazole-treated group (0.50%) compared to the normal group (1.21%; p

CONCLUSION: Omeprazole causes protein-bound vitamin B12 malabsorption, and ingestion of an acidic drink improves protein-bound vitamin B12 absorption.

Pomelo juice, but not cranberry juice, affects the pharmacokinetics of cyclosporine in humans

Posted: 
November 11, 2010
Authors: 
Grenier J, Fradette C, Morelli G, Merritt GJ, Vranderick M, Ducharme MP
Journal: 
Clin Pharmacol Ther 79(3):255-62
Abstract: 

BACKGROUND: Cyclosporine (INN, ciclosporin) is a cytochrome P450 (CYP) 3A and P-glycoprotein (P-gp) substrate whose bioavailability increases when administered with grapefruit juice. It is unknown whether pomelo, a closely related citrus fruit, interacts with cyclosporine in humans. In addition, a case study reports that cranberry juice interacts with warfarin, a drug with a narrow therapeutic range. Cranberries have a high content of flavonoids, compounds with various metabolic effects, including interaction with P-gp in vitro. Although the effect of flavonoids is less evident in vivo, cranberry juice has become a very popular beverage, and it was deemed important to investigate whether it has an effect on the disposition of cyclosporine, another drug with a narrow therapeutic range.

METHODS: In an open-label, randomized, 3-way crossover study with a 14-day washout period between each dose, 12 healthy male volunteers received single oral 200-mg doses of cyclosporine according to the following regimens: 200 mg cyclosporine administered with 240 mL of pomelo juice, cranberry juice, or water under fasting conditions. Multiple whole blood samples were collected up to 36 hours after each dose. Concentrations were determined via a liquid chromatography-tandem mass spectrometry method.

RESULTS: Administration of pomelo juice with cyclosporine increased the area under the curve from time 0 to the last measurable concentration (AUCt), area under the curve from time 0 to infinity (AUCinf), and maximum blood concentration (Cmax) of cyclosporine with ratios of least squares means of 119.4% (95% confidence interval [CI], 113.4%-125.8%), 118.9% (95% CI, 113.8%-124.3%), and 112.1% (95% CI, 102.3%-122.8%), respectively. All 3 variables exhibited statistically significant increases (with Bonferroni adjustment), with P = .0001 for AUCt and AUCinf and P = .0167 for Cmax; however, only the increase in AUCt was judged to be clinically significant with a 95% CI outside the 80% to 125% boundaries. Cranberry juice had no clinically significant effect on the overall disposition of cyclosporine. After administration of cyclosporine with cranberry juice, the ratios of least squares means for AUCt, AUCinf, and Cmax for cyclosporine were 95.0% (95% CI, 90.3%-100.1%), 93.4% (95% CI, 89.2%-97.8%), and 95.2% (95% CI, 86.9%-104.2%), respectively.

CONCLUSION: These results suggest that pomelo juice increases the bioavailability of cyclosporine, possibly by inhibiting CYP3A or P-gp activity (or both) in the gut wall. However, drinking a glass of cranberry juice does not appear to significantly influence the disposition of cyclosporine.

Efficacy of cranberry juice on Helicobacter pylori infection: a double-blind, randomized placebo-controlled trial

Posted: 
November 10, 2010
Authors: 
Zhang L, Ma J, Pan K, Go VL, Chen J, You WC
Journal: 
Helicobacter 10(2):139-45
Abstract: 

BACKGROUND: Helicobacter pylori infection is a major cause of peptic ulcer disease and gastric cancer. This study postulated that cranberry juice would be effective in the suppression of H. pylori in an endemically infected population at high risk for gastric cancer.MATERIALS AND METHODS: A prospective, randomized, double-blind, placebo-controlled trial was conducted in Linqu County of Shandong Province, China, where 189 adults aged 48.9 +/- 11.2 years (mean +/- SD) with H. pylori infection were randomly divided into two groups: cranberry juice (n = 97) and placebo (n = 92). Participants were assigned to orally receive two 250-ml juice boxes of cranberry juice or matching placebo beverage daily for 90 days. The degree of H. pylori infection was determined using the 13C-urea breath test before randomization at 35 and 90 days of intervention to assess the efficacy of cranberry juice in alleviating infection.RESULTS: A total of 189 subjects with positive 13C-urea breath test results prior to randomization completed the study. At day 35 of intervention, 14 of the 97 (14.43%) from the the cranberry juice treatment group and 5 of the 92 (5.44%) of the placebo recipients had negative 13C-urea breath test results. After 90 days, the study concluded that 14 of the 97 subjects in the cranberry juice treatment group versus 5 of the 92 in the placebo group yielded negative test results. Eleven individuals from the cranberry juice treatment group and only two from the placebo group were negative at 35 and 90 days of experiment. These results are significant (p

Cranberry does not affect prothrombin time in male subjects on warfarin.

Posted: 
November 9, 2010
Authors: 
Li Z, Seeram NP, Carpenter CL, Thames G, Minutti C, Bowerman S.
Journal: 
J Am Diet Assoc 106(12):2057-61
Abstract: 

There have been case reports suggesting that cranberry beverages may interact with warfarin. To date, no research study has been conducted to examine the potential interaction of cranberry and warfarin. The current study is a randomized, placebo-controlled, double-blind, crossover study to investigate the effect of cranberry juice on prothrombin time as assessed by the international normalized ratio (INR). Seven subjects with atrial fibrillation on a stable dose of warfarin for 3 months were randomized to consume 250 mL of cranberry juice for 7 days, then placebo for 7 days, or vice versa. The washout period was 7 days. The prothrombin time/INR was measured at baseline, and on days 2, 4, 7, 10, 14, 16, 18, 21, and 24. Data were analyzed by the Student t test for paired values. The baseline INR was 2.28+/-0.54 for the cranberry group and 2.13+/-0.50 for the placebo group. For all test points, the INR did not change significantly from baseline. At day 7 on cranberry juice, the INR was 2.23+/-0.53 for cranberry first group and 2.16+/-0.40 for placebo first group. The mean differences between the cranberry and placebo groups were not statistically significant. Our results suggest no significant interaction between the daily consumption of 250 mL cranberry juice and warfarin. When counseling patients on dietary changes necessary during warfarin treatment, it does not seem necessary to eliminate daily cranberry juice consumption at amounts of 250 mL, but the INR should be followed up closely.

Effects of daily ingestion of cranberry juice on the pharmacokinetics of warfarin, tizanidine, and midazolam--probes of CYP2C9, CYP1A2, and CYP3A4

Posted: 
November 9, 2010
Authors: 
Lilja JJ, Backman JT, Neuvonen PJ
Journal: 
Clin Pharmacol Ther 81(6):833-9
Abstract: 

Case reports suggest that cranberry juice can increase the anticoagulant effect of warfarin. We investigated the effects of cranberry juice on R-S-warfarin, tizanidine, and midazolam; probes of CYP2C9, CYP1A2, and CYP3A4. Ten healthy volunteers took 200 ml cranberry juice or water t.i.d. for 10 days. On day 5, they ingested 10 mg racemic R-S-warfarin, 1 mg tizanidine, and 0.5 mg midazolam, with juice or water, followed by monitoring of drug concentrations and thromboplastin time. Cranberry juice did not increase the peak plasma concentration or area under concentration-time curve (AUC) of the probe drugs or their metabolites, but slightly decreased (7%; P=0.051) the AUC of S-warfarin. Cranberry juice did not change the anticoagulant effect of warfarin. Daily ingestion of cranberry juice does not inhibit the activities of CYP2C9, CYP1A2, or CYP3A4. A pharmacokinetic mechanism for the cranberry juice-warfarin interaction seems unlikely.

Pharmacodynamic interaction of warfarin with cranberry but not with garlic in healthy subjects2

Posted: 
November 9, 2010
Authors: 
Mohammed Abdul MI, Jiang X, Williams KM, Day RO, Roufogalis BD, Liauw WS, Xu H, McLachlan AJ
Journal: 
Br J Pharmacol 154(8):1691-700
Abstract: 

BACKGROUND AND PURPOSE: Patients commonly take complementary medicines in conjunction with warfarin yet evidence supporting the safety or the risk of a herb-drug interaction is lacking. The aim of this study was to investigate the possible impact of two commonly used herbal medicines, garlic and cranberry, on the pharmacokinetics and pharmacodynamics of warfarin in healthy male subjects.

EXPERIMENTAL APPROACH: An open-label, three-treatment, randomized crossover clinical trial was undertaken and involved 12 healthy male subjects of known CYP2C9 and VKORC1 genotype. A single dose of 25 mg warfarin was administered alone or after 2 weeks of pretreatment with either garlic or cranberry. Warfarin enantiomer concentrations, INR, platelet aggregation and clotting factor activity were measured to assess pharmacokinetic and pharmacodynamic interactions between warfarin and herbal medicines.

KEY RESULTS: Cranberry significantly increased the area under the INR-time curve by 30% when administered with warfarin compared with treatment with warfarin alone. Cranberry did not alter S- or R-warfarin pharmacokinetics or plasma protein binding. Co-administration of garlic did not significantly alter warfarin pharmacokinetics or pharmacodynamics. Both herbal medicines showed some evidence of VKORC1 (not CYP2C9) genotype-dependent interactions with warfarin, which is worthy of further investigation.

CONCLUSIONS AND IMPLICATIONS: Cranberry alters the pharmacodynamics of warfarin with the potential to increase its effects significantly. Co-administration of warfarin and cranberry requires careful monitoring.

Anthocyanins are bioavailable in humans following an acute dose of cranberry juice

Posted: 
November 8, 2010
Authors: 
Milbury PE, Vita JA, Blumberg JB
Journal: 
J Nutr 140(6):1099-1104
Abstract: 

Research suggests that anthocyanins from berry fruit may affect a variety of physiological responses, including endothelial function, but little information is available regarding the pharmacokinetics of these flavonoids in humans. To determine the pharmacokinetics of cranberry anthocyanins, a study was undertaken in 15 participants (age: 62 +/- 8 y) with coronary artery disease. Blood and urine samples were collected between baseline (0 h) and 4 h after consumption of 480 mL cranberry juice (54% juice; 835 mg total polyphenols; 94.47 mg anthocyanins). Marked inter-individual differences in plasma anthocyanin pharmacokinetics were observed with maximum anthocyanin concentrations detected between 1 and 3 h. Cranberry anthocyanins were bioavailable but with notable differences in the maximum concentration and area under the curve(0-4h) between individual participants. The pattern of anthocyanin glucosides observed in plasma and urine generally reflected the relative concentration determined in the juice. Plasma concentrations of the individual anthocyanins ranged between 0.56 and 4.64 nmol/L. Total recovery of urinary anthocyanin was 0.79 +/- 0.90% of the dose delivered. These data are in agreement with the pharmacokinetics of anthocyanins from other foods suggesting that cranberry anthocyanins are poorly absorbed and rapidly removed from plasma. Observed concentrations of plasma anthocyanins appear insufficient to alter radical load or redox potential but may be adequate to affect signal transduction and/or gene expression.

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