The bottom line is that the effects of Q10 supplement- ation remain unclear, as there is no reliable scientific evidence showing that Q10 supplements improve immune function in people with HIV infection. Subscribers may read the HIV Nutrition Update article noted above for a comprehensive review of Q10. Q10 appeared safe in controlled studies using up to 200 mg daily for 12 months or 100 mg daily for 6 years. Besides a possible elevation of liver enzymes, Q10 may lower blood sugar or decrease blood pressure and interact with medications or other dietary supplements. (1-4) Variability in absorption and interactions among medications, recreational drugs and nutrients may increase or decrease drug or Q10 blood levels. People with decreased liver function, diabetes or hypoglycemia, or those taking other dietary supplements or medications should always consult with their health care provider before taking Q10. A list of herbs that may affect blood sugar levels such as Q10 is available at the Herb-Drug Interaction Handbook web site. People with low blood pressure or taking blood pressure medications may also have to adjust Q10 dosage as appropriate. The safety of Q10 is not established in children, during pregnancy or lactation. People with bleeding disorders or those who take drugs that increase the risk of bleeding, should be aware that Q10 is structurally related to vitamin K, and may interfere with warfarin therapy. Four cases of undesired blood clotting in warfarin-treated patients taking Q10 have been reported. (3) The Vitaline 100 mg and 200 mg wafer product used in the Parkinson’s clinical trial contains a high dose of vitamin E. Patients on supplemental vitamin E or those taking Agenerase should avoid this wafer product due to its increased vitamin E content. Also, the anti-parasitic agent atovaquone (Mepron) used against Pneumocystis Carinii Pneumonia is a Q10 analogue. There was no information on effects of atovaquone on Q10 levels prior to publication of the above noted atricle.

The studies available indicate there is inadequate information on the impact of HIV infection on Q10 metabolism and they lack evidence that Q10 supplementation repletes deficient levels. There is also no data on the potential impact of antiretrovirals or highly active antiretroviral therapy (HAART) on these same parameters. Consequently, at this time, there is no evidence to support the contention that Q10 supplementation slows HIV/AIDS progression. However, independent of its potential role in HIV infection, evidence exists that Q10 metabolism may be impacted by conventional therapies of other HIV-related conditions. For example, both oral antidiabetic and the hypocholesterolemic class of agents, HMG CoA reductase inhibitors, are reported to interfere with Q10 synthesis. Several reviews contain reports of efficacious use of adjunctive Q10 for management of heart failure. Based on these reports, use of Q10 could be considered for HIV-positive people taking HMG CoA reductase inhibitors or for whom a cardioprotective agent may be beneficial. Additional studies are clearly needed to clarify the role of Q10 in HIV infection.

It is important to note, Q10 supplements are not required to undergo testing or manufacturing controls and some versions sold in stores may not contain potentially beneficial amounts of the compound. Also, there may be composition variations from one batch to another and manufacturers may sell poor quality products. To increase the likelihood of securing a reliable Q10 product consumers can visit Consumer Labs to see a list of Q10 products that passed or failed their review.
References

1. Pelton R, LaValle JB, Hawkins EB, Krinsky DL, Editors. Drug-Induced Nutrient Depletion Handbook 1999-2000. Lexi-Comp:Hudson, OH; 1999:256-259.

2. CoEnzyme Q10. Natural Standard Patient Monograph. University of Texas M. D. Anderson Cancer Center; September 2002 (accessed 27 Feb 2003).

3. Heck AH, DeWitt BA, Lukes AL. Potential Interactions Between Alternative Therapies And Warfarin. Am J Health-Syst Pharm 2000;57;1221-1227.

4. Herr SM. Herb-Drug Interaction Handbook. Second edition. Nassau, NY: Church Street Books; 2002.