• Acebutolol
  
• Atenolol
  
• Betaxolol
  
• Bisoprolol
  
• Carteolol
  
• Celiprolol
  
• Esmolol
  
• Labetolol
• Levobetaxolol
  
• Levobunolol
  
• Metipranolol
  
• Metoprolol
  
• Nadolol
  
• Penbutolol
  
• Pindolol
  
• Propranolol
  
• Sotalol
  
• Timolol
  

Beta-adrenergic blockers, particularly propranolol, inhibit myocardial CoQ10- succinoxidase and CoQ10-NADH-oxidase; both enzymes are important for cardiac function (Kishi et al. 1975). Some of the adverse myocardial reactions associated with beta-blocker therapy may be related to depletion of these enzymes. Metoprolol and timolol are less inhibitory than propranolol.

Although CoQ10 is manufactured by the body, deficiencies occur in some physiological and pathological conditions (Artuch et al. 1999). CoQ10 deficiency may be related to certain conditions such as gingivitis (Nakamura et al. 1974); breast cancer (Jolliet et al. 1998); congestive heart failure (Munkholm et al. 1999); angina pectoris (Kamikawa et al. 1985); acute myocardial infarction (Singh et al. 1998); mitochondrial encephalomyopathies (Chan et al. 1998); hypertension, and cardiac function (Singh et al. 1999). In addition, CoQ10 depletion may contribute to aging and photoaging (Hoppe et al. 1999). Low levels of CoQ10 may also compromise immune function (Folkers et al. 1993) and play a role in male infertility (Overvad et al. 1999).

Daily doses of coenzyme Q10 as high as 200 mg for periods of 6 to 12 months or 100 mg for up to 6 years have not been associated with reports of serious adverse effects in clinical studies (Overvad et al. 1999).

Note: Administration of CoQ10 (90 mg po) with ocular timolol in 16 glaucoma patients mitigated the cardiovascular side effects of the drug by delaying inotropic blockade and minimizing chronotropic blockade without affecting intraocular pressure (Takahashi et al. 1989).

Propranolol can reduce the synthesis as well as plasma levels of endogenous melatonin significantly; effects may be less pronounced with chronic beta-blocker therapy (Arendt et al. 1985; Rommell and Demisch 1994). These changes did not affect subjective sleep quality.

Alterations in melatonin levels have been associated with disturbances in the sleep-wake cycle and jet lag (Avery et al. 1998).

Optimal doses for melatonin therapy have not been established (Avery et al. 1998). Commonly available doses range from 0.3 to 5 mg. Physiological blood levels are achieved with doses of 0.3 mg; higher doses (1 mg) result in supraphysiological levels of melatonin in the blood. The efficacy of melatonin supplementation is dependent upon the time of administration, as effects are related to circadian rhythms.

This information is intended to serve as a concise reference for healthcare professionals to identify substances that may be depleted by many commonly prescribed medications. Depletion of these substances depends upon a number of factors including medical history, lifestyle, dietary habits, and duration of treatment with a particular medication. The signs and symptoms associated with deficiency may be nonspecific and could be indicative of clinical conditions other than deficiency. The material presented in these monographs should not in any event be construed as specific instructions for individual patients.

Arendt J, Bojkowski C, Franey C, Wright J, Marks V. Immunoassay of 6-hydroxymelatonin sulfate in human plasma and urine: abolition of the urinary 24-hour rhythm with atenolol. J Clin Endocrin Metab. 1985;60:1166-1173.

Artuch R, Colome C, Vilaseca MA, et al. [Ubiquinone: metabolism and functions. Ubiquinone deficiency and its implications in mitochondrial encephalopathies. Treatment with ubiquinone]. Rev Neurol. 1999;29(1):59-63.

Avery D, Lenz M, Landis C. Guidelines for prescribing melatonin. Ann Med. 1998;30:122-130.

Chan A, Reichmann H, Kogel A, et al. Metabolic changes in patients with mitochondrial myopathies and effects of coenzyme Q10 therapy. J Neurol. 1998;245(10):681-685.

Folkers K, Morita M, McRee J Jr. The activities of coenzyme Q10 and vitamin B6 for immune responses. Biochem Biophys Res Commun. 1993; 28(19391):88-92.

Hoppe U, Bergemann J, Diembeck W, et al. Coenzyme Q10, a cutaneous antioxidant and energizer. Biofactors. 1999;9(2-4):371-378.

Jolliet P, Simon N, Barre J, et al. Plasma coenzyme Q10 concentrations in breast cancer: prognosis and therapeutic consequences. Int J Clin Pharmacol Ther. 1998;36(9):506-509.

Kamikawa T, Kobayashi A, Yamashita T, et al. Effects of coenzyme Q10 on exercise tolerance in chronic stable angina pectoris. Am J Cardiol. 1985;56(4):247-251.

Kishi H, Kishi T, Folkers K. Bienergetics in clinical medicine. III. Inhibition of coenzyme Q10-enzymes by clinically used anti-hypertensive drugs. Res Commun Chem Pathol Pharmacol. 1975;12(3):533-540.

Kishi T, Watanabe T, Folkers K. Bioenergetics in clinical medicine. XV. Inhibition of coenzyme Q10-enzymes by clinically used adrenergic blockers of beta-receptors. Res Commun Chem Pathol Pharmacol. 1977;17(1):157-164.

Munkholm H, Hansen HH, Rasmussen K. Coenzyme Q10 treatment in serious heart failure. Biofactors. 1999;9(2-4):285-289.

Nakamura R, Littarru GP, Folkers R, et al. Study of CoQ10-enzymes in gingiva from patients with periodontal disease and evidence for a deficiency of coenzyme Q10. Proc Natl Acad Sci USA. 1974;71(4):1456-1460.

Overvad K, Diamant B, Holm L, Holmer G, Mortensen SA, Stender S. Coenzyme Q10 in health and disease. Eur J Clin Nutr. 1999;53:764-770.

Rommell T, Demisch L. Influence of chronic beta-adrenoreceptor blocker treatment on melatonin secretion and sleep quality in patients with essential hypertension. J Neural Transm [Gen Sect]. 1994;95:39-48.

Singh RB, Niaz MA, Rastogi SS, et al. Effect of hydrosoluble coenzyme Q10 on blood pressure and insulin resistance in hypertensive patients with coronary heart disease. J Hum Hypertens. 1999;13(3):203-208.

Singh RB, Wander GS, Rastogi A, et al. Randomized, double-blind placebo-controlled trial of coenzyme Q10 in patients with acute myocardial infarction. Cardiovasc Drugs Ther. 1998;12(4):347-353.

Takahashi N, Iwasaka T, Sugiura T, et al. Effect of coenzyme Q10 on hemodynamic response to ocular timolol. J Cardiovasc Pharmacol. 1989;14(3):462-468.