Interactions with Dietary Supplements
Coenzyme Q10
In patients with high cholesterol, simvastatin
therapy results in decreased serum coenzyme Q10 (CoQ10) levels.1 2
Several trials, including double-blind trials, have confirmed this effect of simvastatin and
other HMG-CoA reductase inhibitors, such as lovastatin
and pravastatin.3 4 5
Supplementation with 100 mg6 per day or 10 mg three times daily7 of
CoQ10 has been shown to prevent reductions in blood levels of CoQ10 due to simvastatin. In the
latter study, people taking CoQ10 along with simvastatin increased their blood CoQ10
concentration by 63%. Many doctors recommend that people taking HMG-CoA reductase inhibitor
drugs such as simvastatin also supplement with approximately 100 mg CoQ10 per day, although
lower amounts, such as 10–30 mg per day might conceivably be effective in preventing the
decline in CoQ10 levels.
The omega-3 fatty acid EPA, present in fish oil, may
improve the cholesterol- and
triglyceride-lowering effect of simvastatin. In a preliminary trial, people with high
cholesterol who had been taking simvastatin for about three years were able to significantly
lower their triglyceride levels and raise their levels of HDL (“good”) cholesterol
by supplementing with either 900 mg or 1800 mg of EPA for three months in addition to
simvastatin.8 The authors of the study concluded that the combination of
simvastatin and EPA may prevent coronary heart disease better than simvastatin alone.
Niacin
Niacin is the form of vitamin B3 used to lower cholesterol. Taking large amounts of niacin
along with HMG-CoA reductase inhibitors may cause muscle disorders (myopathy) that can become
serious (rhabdomyolysis).9 10 Such problems appear to be
uncommon.11 12 Moreover, concurrent use of niacin has been reported to
enhance the cholesterol-lowering effect of HMG-CoA reductase inhibitors.13
14 Individuals taking simvastatin should consult a doctor before taking niacin.
Vitamin A
A study of 37 people with high cholesterol
treated with diet and HMG-CoA reductase inhibitors found blood vitamin A levels increased over
two years of therapy.15 Until more is known, people taking HMG-CoA reductase
inhibitors, including simvastatin, should have blood levels of vitamin A monitored if they
intend to supplement vitamin A.
Vitamin E
In a study of seven patients with hypercholesterolemia, eight weeks of simvastatin plus
vitamin E 300 IU improved markers of blood vessel elasticity more than simvastatin
alone.16
Antioxidants
In another study, daily supplementation with a combination of antioxidants (800 IU of vitamin
E, 1,000 mg of vitamin C, 25 mg of beta-carotene, and 100 mcg of selenium) blocked the
beneficial effect of simvastatin-plus-niacin on HDL cholesterol levels.17 Although
there is evidence that some or all of these nutrients may help prevent heart disease,
individuals taking simvastatin who wish to take antioxidants should discuss the use of these
supplements with their doctor.
References
1. Laaksonen R, Jokelainen K, Sahi T, et al. Decreases in serum
ubiquinone concentrations do not result in reduced levels in muscle tissue during short-term
simvastatin treatment in humans. Clin Pharmacol Ther 1995;57:62–6.
2. Laaksonen R, Ojala JP, Tikkanen MJ, et al. Serum ubiquinone
concentrations after short- and long-term treatment with HMG-CoA reductase inhibitors. Eur
J Clin Pharmacol 1994;46:313–7.
3. Ghirlanda G, Oradei A, Manto A, et al. Evidence of plasma
CoQ10-lowering effect by HMG-CoA reductase inhibitors: a double-blind, placebo-controlled
study. J Clin Pharmacol 1993;33:226–9.
4. Watts GF, Cummings MH, Umpleby M, et al. Simvastatin decreases the
hepatic secretion of very-low-density lipoprotein apolipoprotein B-100 in heterozygous
familial hypercholesterolaemia: pathophysiological and therapeutic implications. Eur J
Clin Invest 1995;25:559–67.
5. Folkers K, Langsjoen P, Willis R, et al. Lovastatin decreases coenzyme
Q levels in humans. Proc Natl Acad Sci USA 1990;87:8931–4.
6. Bargossi AM, Grossi G, Fiorella PL, et al. Exogenous CoQ10
supplementation prevents plasma ubiquinone reduction induced by HMG-CoA reductase inhibitors.
Molec Aspects Med 1994;15(suppl):s187–93.
7. Miyake Y, Shouzu A, Nishikawa M, et al. Effect of treatment with
3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors on serum coenzyme Q10 in diabetic
patients. Arzneimittelforschung 1999;49:324–9.
8. Nakamura N, Hamazaki T, Ohta M, et al. Joint effects of HMG-CoA
reductase inhibitors and eicosapentaenoic acids on serum lipid profile and plasma fatty acid
concentrations in patients with hyperlipidemia. Int J Clin Lab Res
1999;29:22–5.
9. Garnett WR. Interactions with hydroxymethylglutaryl-coenzyme A
reductase inhibitors. Am J Health Syst Pharm 1995;52:1639–45.
10. Yee HS, Fong NT. Atorvastatin in the treatment of primary
hypercholesterolemia and mixed dyslipidemias. Ann Pharmacother
1998;32:1030–43.
11. Jacobson TA, Amorosa LF. Combination therapy with fluvastatin and
niacin in hypercholesterolemia: a preliminary report on safety. Am J Cardiol
1994;73:25D–9D.
12. Jokubaitis LA. Fluvastatin in combination with other lipid-lowering
agents. Br J Pract Suppl 1996;77A:28–32.
13. Davignon J, Roederer G, Montigny M, et al. Comparative efficacy and
safety of pravastatin, Nicotinic acid and the two combined in patients with
hypercholesterolemia. Am J Cardiol 1994;73:339–45.
14. Jacobson TA, Jokubaitis LA, Amorosa LF. Fluvastatin and niacin in
hypercholesterolemia: a preliminary report on gender differences in efficacy. Am J
Med 1994;96(suppl 6A):64S–8S.
15. Muggeo M, Zenti MG, Travia D, et al. Serum retinol levels throughout
2 years of cholesterol-lowering therapy. Metabolism 1995;44:398–403.
16. Neunteufl T, Kostner K, Katzenschlager R, et al. Additional benefit
of vitamin E supplementation to simvastatin therapy on vasoreactivity of the brachial artery
of hypercholesterolemic men. J Am Coll Cardiol 1998;32:711–6.
17. Cheung MC, Zhao XQ, Chait A, et al. Antioxidant supplements block the
response of HDL to simvastatin-niacin therapy in patients with coronary artery disease and low
HDL. Arterioscler Thromb Vasc Biol 2001;21:1320–6.
18. Threlkeld DS, ed. Diuretics and Cardiovasculars, Antihyperlipidemic
Agents, HMG-CoA Reductase Inhibitors. In Facts and Comparisons Drug Information. St.
Louis, MO: Facts and Comparisons, Sep 1998, 172.
Copyright © 2004 Healthnotes, Inc. All rights reserved.
www.healthnotes.com
Please read the disclaimer
about the limitations of the information provided here. Do NOT rely solely on the information
in this article.
Learn more about Healthnotes, the company.
Learn more about the authors of Using
Medicines with Vitamins and Herbs
The information presented in Healthnotes is for informational
purposes only. It is based on scientific studies (human, animal, or in vitro),
clinical experience, or traditional usage as cited in each article. The results reported may
not necessarily occur in all individuals. For many of the conditions discussed, treatment with
prescription or over-the-counter medication is also available. Consult your doctor,
practitioner, and/or pharmacist for any health problem and before using any supplements or
before making any changes in prescribed medications. Information expires March 2005.