CoQ10 Side Effects: What You Need to Know Before Taking It (2025)

What is Co Q10?

Coenzyme Q10 or CoQ10 or ubiquinone is a molecule synthesized in the human body and serves as a catalytic helper for crucial energy processes ¹. This coenzyme is primarily involved with cellular energy generation and, because of its health promoting properties, can be purchased without prescription and is found in many formulations for different health benefits including cardiovascular health, energy production and antioxidant protection ². However, certain points should be taken into consideration with regards to its side effects; specifically, CoQ10 may interact with certain medications and, at worst, can cause mild gastrointestinal symptoms.

Coenzyme Q10 acts as an antioxidant, which protects cells from damage and plays an important part in your metabolism.

Coenzyme Q10 levels decrease in your body decrease as you age. Coenzyme Q10 levels have also been found to be lower in people with certain conditions, such as heart disease, and in those who take cholesterol-lowering drugs called statins. Low levels of CoQ10 are also associated with chronic obstructive pulmonary disease (COPD). CoQ10 deficiency is also associated with neurodegenerative disorders such as Parkinson’s and consuming CoQ10 may be useful in slowing the progression of these neurodegenerative diseases. This reduction can lead to all sorts of problems to the health of a person starting from gum diseases, because the cells in the tissue of the mouth require energy and protection from free radicals to perform their functions properly.

Mechanism of Action

When it comes to creating energy in the body, coenzyme Q10 (CoQ10) is a powerhouse. CoQ10 acts as a coenzyme for a number of enzymes in the electron transport chain, and in that role is crucial to the functioning of the mitochondria (where oxidation occurs)—the energy factories of our cells ³ . This is a crucial process converting carbohydrates, fats and proteins to adenosine triphosphate (ATP) the body’s main energy currency.

Coenzyme Q10 Foods and Dietary Supplements

While many people’s bodies make all the Coenzyme Q10 they need, some don’t. The whole body content is between 500 and 1,500 milligrams, and it decreases with age.

Good food sources of CoQ10 include:

Organ meats. Coenzyme Q10 is present in cells throughout your body, mostly concentrated in your vital organs. This means animal organ meats have the highest amounts of Coenzyme Q10 per 100 grams. For instance, a beef heart has 11.3 milligrams, and a beef liver has 3.9 milligrams. A chicken heart has 9.2 milligrams and liver has 11.6 milligrams. ⁴

Fatty fish. Fatty fish such as trout, salmon, mackerel, and sardines contain Coenzyme Q10. Mackerel provides about 6.75 milligrams per 100 grams while trout provides 0.85 milligrams per 100 grams.

Meat. It’s not just animal organs that provide Coenzyme Q10. Because it lives throughout your body, it’s present in all meat forms. Beef offers about 3.1 milligrams per 100 grams, chicken has 1.4 milligrams, and pork has 2.4 milligrams. Reindeer meat provides about 15.8 milligrams.

Soybeans. Soybean products such as tofu, soy milk, and soy yogurt are a valuable protein source. Soybeans also have many other vitamins and minerals, as well as CoQ10. Boiled soybeans have 1.2 milligrams per 100 grams. Other soy products contain a lesser amount of CoQ10, with tofu at 0.3 milligrams and soy milk at 0.25 milligrams.

Vegetables. Along with many vitamins and minerals, a lot of vegetables contain CoQ10. Among them, broccoli has high Coenzyme Q10 content, weighing in at 0.6 to 0.86 milligrams per 100 grams.

Nuts and seeds. Along with protein, heart-healthy fats, and other important nutrients, nuts and seeds provide Coenzyme Q10. Pistachios have 2 milligrams of Coenzyme Q10 per 100-gram serving, peanuts have 2.6 milligrams, and sesame seeds have 1.7 milligrams.

Benefits of Coenzyme Q10

Research on Coenzyme Q10 use for specific conditions and activities shows:

• Heart conditions. Coenzyme Q10 has been shown to improve symptoms of congestive heart failure. Although findings are mixed, Coenzyme Q10 might help reduce blood pressure. Some research also suggests that when combined with other nutrients, Coenzyme Q10 might aid recovery in people who’ve had bypass and heart valve surgeries. Monitoring the blood pressure is recommended. ⁵
• Brain health. Coenzyme Q10 may reduce harmful compounds that could increase your risk of neurodegenerative diseases, such as Alzheimer’s, Parkinson’s disease, and Parkinson’s disease. In turn, this could slow disease progression. ⁶
• Diabetes. There remain some studies, though more extensive ones are necessary, which indicate that Coenzyme Q10 may be effective in decreasing both LDL cholesterol and overall cholesterol among diabetics, and consequently protect them from heart disease.
• Statin-induced myopathy. The published research suggests that Coenzyme Q10 might help alleviate problems of muscle soreness and weakness brought about by the consumption of statins.
• Migraines. One study outlined in this new research suggests that Coenzyme Q10 could lower the rate of occurrence of such headaches.
• Physical Performance. Because Coenzyme Q10 is involved in energy production, it’s believed that this supplement might improve your physical performance. However, research in this area has produced mixed results.
• Fertility. Eggs and sperm are susceptible to oxidative damage. Coenzyme Q10 may help stop, and even reverse, the decline in egg quantity and quality as you age. Studies also show that the compound could improve sperm activity and concentration, boosting fertility.

Coenzyme Q10 and Complementary and Integrative Health

• Coenzyme Q10 is a dietary supplement that can be obtained over-the-counter.
• This supplement comes in capsules, tablets, and soft gels, liquid concentrates as well as powder formulations.
• It can be taken with other nutrients and other drugs to improve health, organ, and muscular strength Coenzyme Q10 can therefore be classified under dietary supplements.

Side Effects and Safety Precautions

Common side effects of Coenzyme Q10 are rare and do not have any severe side effects unless it’s administered in large doses. Most people will not have any side effects at all but some people may develop mild side effects. Common side effects of Coenzyme Q10 include:

• Gastrointestinal Issues:

Nausea: Some people may develop nausea when they are using Coenzyme Q10.

Diarrhea: This may result in diarrhea or loose stools more frequently or apart from the normal signs of constipation at higher doses.

Upset Stomach: It can also lead to mild stomach discomfort.

• Headache: There are rare cases in people using Coenzyme Q10 in that they develop headaches that may be due to vascular changes.
• Dizziness: On very few occasions there may be dizziness or lightheadedness on the part of the patient.
• Insomnia or Sleep Issues: Some patients may experience some disturbances in sleep patterns since this coenzyme supplement may affect their ability to go to sleep or remain asleep while others produce drowsiness or headache when taken late in the evening.
• Allergic Reactions: As with most medications, side effects are uncommon; however, one may develop skin rash or other allergic reactions.
• Low Blood Pressure: Coenzyme Q10 may reduce a person’s blood pressure which, in some cases, is good for patients with high blood pressure but in other cases may result to even hypotension, which inclines a person to suffer from dizzy spells or even faint. ⁷
• Interactions with Medications: Coenzyme Q10 can interfere with some drugs, including blood thinning medications such as warfarin, which is an anticoagulant, as well as most of the drugs that regulate blood pressure and several chemotherapy drugs. It is important to be cautious when taking CoQ10 with these medications due to potential interactions.
• Fatigue or Weakness: While Coenzyme Q10 can be taken to give one more energy, there are people who experience some fatigue or weakness once they start supplementing on it.

Possible interactions include: Anticoagulants. Coenzyme Q10 might make blood-thinning drugs, such as warfarin (Jantoven), less effective. This could in turn increase the chances of forming a blood clot.

Interactions with Medications

• Coenzyme Q10 could interfere with several medicines used for cancer therapies: busulfan, carboplatin, and cisplatin.
• It may also affect levels of warfarin (Coumadin) and raise the likelihood of developing blood clots.
• Coenzyme Q10 may have an interaction with certain drugs for high blood pressure like captopril and enalapril where the blood pressure goes very low.
• It can also have an impact on the reduction of cholesterol-carrying drugs and reduce its efficiency.

Dosage and Administration

• The dose of Coenzyme Q10 depends on the patient and the particular illness that they are suffering from.
• The standard dose of this medication lies between 30 and 100 milligrams per day for an adult and 10 to 30 milligrams per day for children.
• It is well advisable to take Vitamins like Coenzyme Q10 either before or after taking the meal, but it is most effective to take it with a meal so that the gut can effectively absorb it.

Effectiveness in Lowering Blood Pressure

• Coenzyme Q10 may help lower blood pressure and reduce the risk of cardiovascular disease.
• Research has revealed that the effectiveness of Coenzyme Q10 reduces systolic blood pressure and minimizes heart disease.
• It is also known that Coenzyme Q10 can also decrease the probability of congestive heart failure and promote cardiovascular health.

Reviews and Recommendations

• Coenzyme Q10 is generally well-reviewed and recommended by healthcare professionals for its potential health benefits.
• Coenzyme Q10 should best be taken under advice from a health care provider if one has any health condition that is chronic or is on medications.
• Coenzyme Q10 may be beneficial for people with heart disease, high blood pressure, and other cardiovascular conditions.

Precautions for Special Populations

• Coenzyme Q10 is possibly safe for pregnant women, but more research is needed to confirm its safety.
• It is also possibly safe for children when taken under medical supervision.
• Coenzyme Q10 should be avoided during breastfeeding due to a lack of available research.
• People with Parkinson’s disease, gum disease, muscle weakness caused by statin-induced myopathy, and other chronic conditions like Parkinson’s disease may benefit from taking CoQ10.

Monitoring and Adjusting Dosage

• It is suggested that blood pressure should be checked and Coenzyme Q10 dosage lowered if necessary.
• Interactions of Coenzyme Q10 has been known earlier and therefore it is advised to have interactions checked out.
• Practitioners of health care might suggest periodic evaluations in order to determine effectiveness of this Coenzyme Q10 supplement and make changes to dosage if necessary.

Conclusion

Coenzyme Q10 will also be referred to as CoQ10 is this document because it is a naturally occurring substance and a potent antioxidant that is involved in energy production and protection of cells. Though research is still underway, promising findings show that CoQ10 offers multiple health benefits such as; lower risk of heart diseases, enhanced exercise endurance, skin, brain and lung health. Also, there is evidence that CoQ10 can support symptoms of several chronic diseases including Parkinson’s disease, diabetes, and cancer.

It is important to understand though that CoQ10 can interfere with some medications like blood thinners, blood pressure medicines and statins or cholesterol-lowering drugs. As such, it is advisable to seek medical advice before using CoQ10 supplements especially if you’re on some other medication or with other health complications.

The dosage of CoQ10 is in milligrams and ranges from 30-100 milligrams in time for the daily dosage although there are many forms that CoQ10 comes in such as capsules, tablets and liquid syrups. Although CoQ10 is well tolerated, taking it at high doses can lead to side effects including gastrointestinal issues, headaches, and dizziness.

All in all, CoQ10 is a potentially therapeutic dietary supplement with a long list of potential health benefits for a person with chronic illnesses and other health issues. But, also there is a need to use CoQ10 with some form of precaution in this sense, and the best advice, in this sense, is to seek the services of a health professional if interested in using CoQ10.

References:

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