Congestive Heart Failure (CHF) and Coenzyme Q10

Coenzyme Q10 (CoQ10), also known as ubiquinone, is a major part of the body's mechanism for producing energy. People with congestive heart failure (CHF) have significantly lower levels of CoQ10 in heart muscle cells than healthy people.⁴² This fact alone does not prove that CoQ10 supplements will help CHF; however, it prompted medical researchers to try using this supplement as a treatment for heart failure. The results of some of these studies are very promising.

Research demonstrates that the amino acid taurine may be even more effective at treating CHF than CoQ10 is.

The exact effect of CoQ10 on congestive heart failure is not entirely clear. Some evidence suggests that CoQ10 might assist the heart during times of stress on the heart muscle, perhaps by helping it use energy more efficiently.

Read more details about Coenzyme Q10.

In the largest study, 641 individuals with moderate to severe congestive heart failure (CHF) were monitored for 1 year.² Half were given 2 mg/kg of body weight of CoQ10 daily; the rest were given placebo. Standard therapy was continued in both groups. The participants treated with CoQ10 experienced a significant reduction in the severity of their symptoms. No such improvement was seen in the placebo group. The people who took CoQ10 also had significantly fewer hospitalizations for heart failure.

Similarly positive results were also seen in other double-blind studies involving a total of more than 270 participants.^37-38,58

However, two recent and very well-designed double-blind studies enrolling a total of about 85 individuals with CHF failed to find any evidence of benefit.^3,41 The reason for this discrepancy is not clear.

The typical recommended dosage of CoQ10 is 30 mg to 300 mg daily; higher daily intakes have been used in some studies. In the studies discusses here, patients were given daily doses of 2 mg per kilogram of body weight.

CoQ10 is fat soluble and may be better absorbed when taken in an oil-based soft gel form rather than in a dry form such as tablets and capsules.¹¹ Dividing the total daily dosage up into two or more separate doses may produce higher blood levels.¹² A finely ground up (“nanoparticular”) form of the supplement appears to be much better absorbed than standard CoQ10 products.¹³

• Integrative MD
• Naturopathic doctor
• Clinical nutritionist or registered dietitian

Safety Issues

In general, CoQ 10 appears to be extremely safe. No significant side effects have been found, even in studies that lasted a year. ¹ However, people with severe heart disease should not take CoQ 10 (or any other supplement) except under a doctor's supervision.

As noted above, two studies suggest that CoQ 10 might reduce blood sugar levels in people with diabetes. ² While this could potentially be helpful for treatment of diabetes, it might present a risk as well; people with diabetes who are using CoQ 10 might inadvertently push their blood sugar levels dangerously low. However, another trial in people with diabetes found no effect on blood sugar control. ³ The bottom line: If you have diabetes, make sure to track your blood sugar closely if you start taking CoQ 10 (or, indeed, any herb or supplement).

CoQ 10 chemically resembles vitamin K . Since vitamin K counters the anticoagulant effects of warfarin (Coumadin), it has been suggested that CoQ 10 may have the same effect. ⁴ However, a small, double-blind study found no interaction between CoQ 10 and warfarin. ⁵ Nonetheless, in view of warfarin’s low margin of safety, prudence indicates physician supervision before combining CoQ 10 with warfarin.

CoQ 10 might also interact with reverse transcriptase inhibitors used for treatment of HIV (for example, lamivudine and zidovudine). These medications can cause damage to the mitochondria, the energy-producing subunits of cells, leading in turn to a variety of side effects, including lactic acidosis (a dangerous metabolic derangement), peripheral neuropathy (injury to nerves in the extremities), and lipodystrophy (cosmetically undesirable rearrangement of fat in the body). The supplement CoQ 10 has been tried for minimizing these side effects, but unexpected results occurred. In a double-blind, placebo-controlled study, use of CoQ10 improved general sense of well-being in people with HIV-infection using reverse transcriptase inhibitors; however, for reasons that are unclear, it actually worsened symptoms of peripheral neuropathy. ⁶ For this reason, people with HIV who have peripheral neuropathy symptoms should use CoQ 10 only with caution.

The maximum safe dosages of CoQ 10 for young children, pregnant or nursing women, or those with severe liver or kidney disease have not been determined.

Interactions You Should Know About

You may need more CoQ 10 if you are taking:

• Cholesterol-lowering drugs in the statin family
• Red yeast rice
• Beta-blockers (specifically propranolol metoprolol , and alprenolol )
• Antipsychotic drugs in the phenothiazine family
• Tricyclic antidepressants
• Methyldopa
• Hydrochlorothiazide
• Clonidine
• Hydralazine
• Oral diabetes drugs (especially glyburide, phenformin, and tolazamide)

You should not take CoQ 10 except on a physician's advice if you are taking:

• Coumadin (warfarin)

CoQ 10 might improve general sense of well-being, but worsen peripheral neuropathy symptoms if you are taking:

• Reverse-transcriptase inhibitors (for HIV infection)

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