CoQ10 for Elevated Blood Pressure

The short answer: CoQ10 (coenzyme Q10) might take a few points off systolic pressure, but it's not a reliable treatment for high blood pressure. A 2025 meta-analysis of 45 randomised trials found systolic pressure 3.44 mmHg lower than with placebo, with no significant change in diastolic pressure or heart rate (Karimi 2025). A 2022 analysis of 26 trials in people with cardiometabolic disease found 4.77 mmHg lower (Zhao 2022).

The trials with the tightest methods are less encouraging. The 2016 Cochrane review pooled two double-blind trials and found moderate-quality evidence of no clinically significant effect (Ho 2016), and a crossover trial using 24-hour monitoring in treated patients found none (Young 2012). We rate it mixed with an effectiveness of 2 out of 5: the body of trials is large, but the effect is small and shrinks as the methods get stricter.

CoQ10 is made by the body and is found in the highest amounts in the heart, liver, kidneys and pancreas (NCCIH). It's an electron carrier that the mitochondria need to make ATP, the cell's energy currency, and it also works as an antioxidant (Sue-Ling 2022).

The usual explanation for a blood pressure effect is that CoQ10 eases oxidative stress (damage from reactive oxygen molecules) in the blood vessel wall, letting vessels relax. Supplements clearly raise blood levels: by about 1.62 µg/mL across trials (Zhao 2022), and 3-fold in a diabetes trial (Hodgson 2002).

Higher blood levels don't show that CoQ10 lowers blood pressure. In the diabetes trial, blood pressure fell while plasma F2-isoprostanes, a standard marker of oxidative stress, didn't change, so the antioxidant theory didn't explain the result (Hodgson 2002). In a 2026 trial, 200 mg of ubiquinol quadrupled blood CoQ10 in older adults without changing measures of cardiovascular health (Nankivell 2026).

Low CoQ10 levels in people with heart disease are also not proof that topping them up helps. Statins lower blood CoQ10 (Banach 2015), yet in statin users, adding CoQ10 didn't change systolic pressure in three of four trials (Flowers 2014).

Most blood pressure trials used 100-200 mg a day, split into two doses: 60 mg twice daily (Burke 2001) or 100 mg twice daily (Hodgson 2002; Young 2012). A dose-response meta-analysis found a U-shaped curve with the largest systolic drop at around 100-200 mg a day (Zhao 2022), and another found doses under 200 mg a day did better than higher ones (Karimi 2025). There's no case for megadoses.

Ubiquinol, the reduced form, is often sold as better absorbed. In 12 healthy volunteers, 200 mg a day of ubiquinol raised plasma CoQ10 to 4.3 µg/mL against 2.5 µg/mL with ubiquinone (Langsjoen 2014). In 21 older adults given a single 100 mg dose, ubiquinol's 1.7-fold advantage wasn't significant, and CoQ10 appeared in the blood mostly as ubiquinol whichever form was taken (Pravst 2020). No trial has compared the two forms on blood pressure.

Karimi 2025 pooled 45 randomised trials in adults: systolic pressure fell 3.44 mmHg more than with placebo (95% CI -5.13 to -1.55), while diastolic pressure (-1.13 mmHg, p = 0.23) and heart rate didn't change significantly. Zhao 2022 pooled 26 trials with 1,831 people with cardiometabolic disease and found systolic pressure 4.77 mmHg lower (95% CI -6.57 to -2.97), larger in diabetes and dyslipidaemia and in trials over 12 weeks; certainty was rated moderate for systolic and low for diastolic pressure. Tabrizi 2018 found the same pattern in 17 trials of people with metabolic diseases: lower systolic pressure, no significant diastolic change.

Earlier estimates were much larger. Rosenfeldt 2007 reported falls of up to 17 mmHg systolic and 10 mmHg diastolic, but eight of its twelve studies were open-label. In a 12-week double-blind trial in 83 people with isolated systolic hypertension, systolic pressure fell 17.8 mmHg in the CoQ10 group, though the abstract doesn't give the difference from placebo (Burke 2001). In 74 people with type 2 diabetes, 200 mg a day lowered blood pressure by 6.1/2.9 mmHg (Hodgson 2002).

The 2009 Cochrane review found falls of 11/7 mmHg in three trials but called the result uncertain because some trials might be unreliable (Ho 2009). Its 2016 update excluded one trial for high risk of bias and pooled the remaining two (50 people): systolic -3.68 mmHg (95% CI -8.86 to 1.49) and diastolic -2.03 mmHg, neither significant, which it judged moderate-quality evidence of no clinically significant effect (Ho 2016).

Trials with 24-hour ambulatory monitoring, which avoids clinic-reading bias, were also null. In 30 people with metabolic syndrome and uncontrolled pressure on medicines, 100 mg twice daily didn't lower 24-hour systolic (P = 0.60) or diastolic pressure (P = 0.12) (Young 2012). In 85 people with chronic kidney disease, 200 mg a day had no effect on blood pressure and raised heart rate, while omega-3 lowered both (Mori 2009). A 2026 meta-analysis of 20 trials in prediabetes and type 2 diabetes found no significant change in systolic or diastolic pressure (Rezagholizadeh 2026).

No trial has tested whether CoQ10 prevents strokes, heart attacks or deaths in people with high blood pressure. The Cochrane review of CoQ10 for preventing cardiovascular disease found six small trials, none of which reported cardiovascular events or adverse events (Flowers 2014). Most blood pressure trials are small and run for 8-12 weeks, and the populations vary widely, from healthy adults to people with kidney disease.

CoQ10 is well tolerated at the doses studied. NCCIH reports no serious side effects, with occasional insomnia or digestive upset (NCCIH). In the trials it caused no clinically relevant changes in safety tests (Young 2012) and no drops in blood pressure on standing (Burke 2001).

The main risks are an interaction and an opportunity cost. CoQ10 may interact with warfarin and insulin (NCCIH). And a few mmHg is far smaller than what medicines or lifestyle changes achieve; NHLBI notes that many people need two or more medicines to manage high blood pressure (NHLBI).

Standard care does far more. NHLBI recommends a heart-healthy eating plan such as DASH, noting that DASH combined with a low-salt diet can be as effective as medicines; limiting alcohol; regular physical activity, even 10 minutes of walking a day; losing 3-5% of body weight if you're overweight; quitting smoking; managing stress; and 7-9 hours of sleep (NHLBI). When lifestyle changes aren't enough, ACE inhibitors, angiotensin receptor blockers, calcium channel blockers and thiazide diuretics are the next step.

Among supplements, compare potassium for high blood pressure and garlic extract before choosing CoQ10.

One double-blind trial gave 200 mg of CoQ10 a day from 20 weeks of pregnancy to 235 women at increased risk of pre-eclampsia (high blood pressure with organ strain in pregnancy). Pre-eclampsia developed in 14.4% on CoQ10 against 25.6% on placebo (RR 0.56, 95% CI 0.33-0.96), though 16% of women weren't followed up (Teran 2009). It hasn't been repeated. NHLBI advises talking with your provider about blood pressure medicines if you're pregnant or planning to be (NHLBI).

Warfarin is the interaction that matters: CoQ10 may interact with it (NCCIH) and can reduce the body's response to it (NCI). CoQ10 may also lower insulin needs in people with diabetes (NCI).

Statins and some diabetes tablets lower blood CoQ10 levels (NCI; Banach 2015), but that hasn't translated into a blood pressure benefit from adding CoQ10 in statin users (Flowers 2014). In the trials, CoQ10 was taken with a range of blood pressure medicines without safety problems (Young 2012).