Drug & supplement interaction

Coenzyme Q10 + Methyldopa

Methyldopa brand names: Aldomet, Methyldopa.

Minor Interaction
Medically reviewed by · Updated September 2026
The bottom line Minor

Coenzyme Q10 has a minor interaction with Methyldopa. Theoretically, coenzyme Q10 might have additive effects with antihypertensive drugs.

Read the full interaction report
SeverityMinor
LikelihoodPossible
EvidenceB
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Facebook Post Reddit Email
On this page
Interaction report

Coenzyme Q10 and Methyldopa

Here is the interaction we found between these two, with the evidence behind it.

Minor

ANTIHYPERTENSIVE DRUGS

Why this applies to Methyldopa

Methyldopa falls under ANTIHYPERTENSIVE DRUGS — the group Coenzyme Q10 interacts with.

Theoretically, coenzyme Q10 might have additive effects with antihypertensive drugs.
Some clinical research shows that coenzyme Q10 can significantly lower blood pressure, although other studies have shown conflicting results.
Severity Minor Likelihood Possible Evidence B

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the simple version: CoQ10 may gently lower blood pressure on its own. Since methyldopa (Aldomet) is already working to bring your numbers down, taking the two together could add up and push your blood pressure a little lower than expected. This isn't about CoQ10 changing how your liver handles the drug, it's just two things nudging in the same direction.

If your pressure drops too much, you might feel some of methyldopa's familiar effects more strongly, like dizziness, lightheadedness when standing, drowsiness, or fatigue. The evidence here is modest and the effect is usually minor, so don't panic. Still, it's worth telling your pharmacist or doctor, and checking your blood pressure at home so they can adjust things if needed.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Langsjoen P, Willis R, Folkers K. Treatment of essential hypertension with coenzyme Q10. Mol Aspects Med 1994;S265-72. PubMed
  2. Singh RB, Niaz MA, Rastogi SS, et al. Effect of hydrosoluble coenzyme Q10 on blood pressures and insulin resistance in hypertensive patients with coronary artery disease. J Hum Hypertens 1999;13:203-8. PubMed
  3. Burke BE, Neuenschwander R, Olson RD. Randomized, double-blind, placebo-controlled trial of coenzyme Q10 in isolated systolic hypertension. South Med J 2001;94:1112-7. PubMed
  4. Hodgson JM, Watts GF, Playford DA, et al. Coenzyme Q10 improves blood pressure and glycaemic control: a controlled trial in subjects with type 2 diabetes. Eur J Clin Nutr 2002;56:1137-42. PubMed
  5. Digiesi V, Cantini F, Oradei A, et al. Coenzyme Q10 in essential hypertension. Mol Aspects Med 1994;15 Suppl:s257-63. PubMed
  6. Yamagami T, Takagi M, Akagami H, et al. Effect of coenzyme Q10 on essential hypertension, a double blind controlled study. In: Folkers KA, Yamamura Y, eds. Biomedical and Clinical Aspects of Coenzyme Q, Vol. 5. Amsterdam: Elsevier Science Publications, 19
  7. Ho MJ, Bellusci A, Wright JM. Blood pressure lowering efficacy of coenzyme Q10 for primary hypertension (review). Cochrane Database Syst Rev 2009;(4):CD007435. PubMed
  8. Young, J. M., Florkowski, C. M., Molyneux, S. L., McEwan, R. G., Frampton, C. M., Nicholls, M. G., Scott, R. S., and George, P. M. A randomized, double-blind, placebo-controlled crossover study of coenzyme Q10 therapy in hypertensive patients with the me
  9. Digiesi V, Cantini F, and Brodbeck B. Effect of coenzyme Q10 on essential arterial hypertension. Current Therapeutic Research 1990;47(5):841-845.
  10. Ho MJ, Li EC, Wright JM. Blood pressure lowering efficacy of coenzyme Q10 for primary hypertension. Cochrane Database Syst Rev. 2016 Mar 3;3:CD007435. doi: 10.1002/14651858.CD007435.pub3. PubMed
  11. Tabrizi R, Akbari M, Sharifi N, Lankarani KB, Moosazadeh M, Kolahdooz F, et al. The effects of coenzyme Q10 supplementation on blood pressures among patients with metabolic diseases: a systematic review and meta-analysis of randomized controlled trials. PubMed

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Coenzyme Q10 Also Interacts With Other Medications

Coenzyme Q10 has 26 moderate, 171 minor known drug interactions in our database — the Methyldopa one above is one of them. If you take anything else, check it against the full list below.

Moderate 26 Minor 171 No known interaction 2,633 (incl. Methyldopa)
Taking anything else?

Check Another of Your Medications Against Coenzyme Q10

Covers the 2,830 medications we’ve checked against Coenzyme Q10. Pick one to open its full report.

From our Q&A

Questions About Coenzyme Q10 or Methyldopa

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Coenzyme Q10 or Methyldopa, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Methyldopa

This page covers Coenzyme Q10 only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Methyldopa page lists 173 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), American Mistletoe (major), Beer (major) and Cowhage (major).

By severity: 8 major · 144 moderate · 21 minor.

From our pharmacist’s overview on the Methyldopa page

“Alcohol is the entry I would read first. Methyldopa (Aldomet) can be hard on the liver by itself, and 38 of the 173 supplement and herbal ingredients here, beer and wine included, carry liver risks that could stack on top of that.”

Reviewed by 2 · Jul 18, 2026

Open the Methyldopa interaction page

One more smart check

Taking Coenzyme Q10 as Part of a Dietary Supplement Product? Check It for Interactions

We hold 6,926 real supplement products containing Coenzyme Q10, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Coenzyme Q10. Your product may carry other ingredients that interact with Methyldopa too, on top of Coenzyme Q10 — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Coenzyme Q10 and Methyldopa Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Coenzyme Q10
Top 5%

#36 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Methyldopa
Steady interest

#1,778 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Coenzyme Q10

What is Coenzyme Q10?

  • Heart health
  • Statin-related muscle aches
  • Migraine prevention
  • Energy and fatigue
  • Aging and antioxidant support

CoQ10 is a vitamin-like substance your body makes naturally that helps cells produce energy and acts as an antioxidant. It is generally well tolerated and is most studied for heart conditions, statin-related muscle symptoms, and migraine prevention, though the strength of the evidence varies. Talk with your pharmacist or doctor before starting it, especially if you take heart or blood pressure medicines.

Read the full Coenzyme Q10 monograph & all interactions
Medication

About Methyldopa

What Is Methyldopa Used For?

Brand names: Aldomet, Methyldopa

Methyldopa tablets are used to treat high blood pressure (hypertension) in adults and children. Lowering blood pressure reduces the risk of complications that come with uncontrolled hypertension.

See full Methyldopa drug information
Keep checking

Other Drugs & Coenzyme Q10

Browse every other medication we’ve checked against Coenzyme Q10 — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
26Moderate
171Minor
2,632No known interaction
26 Moderate 171 Minor 2,632 No interaction
Moderate

26 interactions

Minor

171 interactions

Showing 60 of 171 minor interactions — see all 171 on the Coenzyme Q10 page.

No interaction 2,632 drugs checked — show the list

We also checked Coenzyme Q10 against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,632 medications checked with no known interaction — see the full Coenzyme Q10 list.

See the full Coenzyme Q10 interactions page
See every supplement checked against Methyldopa, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

Keep exploring
Coenzyme Q10 monograph › Uses, safety, and every drug interaction in one place Methyldopa supplement interactions › Every supplement checked against Methyldopa, ranked by severity Methyldopa drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Coenzyme Q10 and Methyldopa Together: Common Questions

Can you take Coenzyme Q10 with Methyldopa?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Coenzyme Q10 and Methyldopa interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Methyldopa and Coenzyme Q10?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.