Is Black Seed Oil Safe With Metoprolol And Flecainide?
In our latest question and answer, our pharmacist discusses whether or not there are interactions between black seed oil, metoprolol and flecainide.
I am taking flecainide and metoprolol and wanted to know if it’s safe to take black seed oil.
Jan 30, 2023- Black seed oil may lower blood pressure, which could add to the blood pressure-lowering effect of metoprolol and potentially cause dizziness or lightheadedness.
- There is no clear evidence of an interaction between black seed oil and flecainide, though research on this combination is limited.
- You should tell your doctor about taking black seed oil with these medications so your blood pressure and overall condition can be monitored.
Answer
Black seed oil supplements do have some interactions to be aware of, so I'm glad you reached out to us!
When answering questions like this, I always like to put forth the caveat that drug-herb interactions can be difficult to predict.
Drug-herb interactions not only have limited data behind them but can often depend on many factors, such as the dose and preparation of the herbal in question, as well as individual factors such as genetics and overall medical condition.
Nevertheless, let's get into your question about metoprolol and flecainide.
Black Seed Oil May Lower Blood Pressure
The primary concern between black seed oil supplements and blood pressure medication, like metoprolol, is the additive blood pressure-lowering effects.
Metoprolol is a beta-blocker that, among other things, lowers blood pressure. Black seed oil has been reported to have a mild blood pressure-lowering effect as well. One study reported:
Our meta-analysis suggests that short-term treatment with N. sativa powder can significantly reduce SBP [systolic blood pressure] and DBP [diastolic blood pressure] levels. More evidence is needed, however, to strengthen the available evidence and to further explore the long-term BP-lowering effect of N. sativa.
Please note that N. sativa stands for Nigella sativa, the scientific name for black seed.
So, theoretically, combining metoprolol and black seed oil could drop blood pressure too low. This could increase the risk of side effects, such as dizziness, sedation, and lightheadedness.
On the other hand, you could think of this interaction as a positive thing, helping to get blood pressure more under control if it is currently too high.
The important thing is that you know both can lower blood pressure and you monitor it appropriately. You should also let your doctor know of all the drugs and supplements you are taking so you can be monitored as well.
Based on the mechanism of this interaction, our 'drug-herbal interaction checker' will return a result with any blood pressure medication, such as:
What About Flecainide?
I could not find any information supporting a potential interaction between black seed oil and flecainide, a medication used to treat arrhythmias.
However, in line with the caveat I wrote about above, there is limited research on the potential interactions between flecainide and black seed. There is no clear evidence of any significant interactions but, as with any supplement or medication, it is always best to consult with your doctor before starting or stopping any new regimen so you can be assessed and monitored.
Final Words
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References & sources
- Antihypertensive effect of Nigella sativa seed extract in patients with mild hypertension — PubMed
- A systematic review and meta-analysis of randomized controlled trials investigating the effects of supplementation with Nigella sativa (black seed) on blood pressure — PubMed
- Metoprolol Tartrate Monograph — PubChem
- Flecainide Monograph — PubChem
Glossary — Terms in This Answer
- Beta-blocker
- A type of medication that slows heart rate and lowers blood pressure by blocking certain nerve signals.
- Systolic blood pressure
- The higher number in a blood pressure reading that measures pressure in arteries when the heart beats.
- Diastolic blood pressure
- The lower number in a blood pressure reading that measures pressure in arteries when the heart is resting between beats.
- Meta-analysis
- A statistical study that combines results from multiple research studies to reach an overall conclusion.
- Drug-herb interactions
- Unwanted changes that occur when medications and herbal supplements work together in the body.
- Additive effects
- When two substances combine to create a stronger total effect than either one alone would produce.
- Arrhythmias
- Irregular heartbeats or abnormal patterns in how the heart beats.
- Nigella sativa
- The scientific name for the black seed plant used to make black seed oil supplements.
Dr. Brian Staiger, PharmD
Doctor of Pharmacy, board certified clinical pharmacist (BCPS), American Herbalist Guild, Medication Therapy Management certified
Brian Staiger, PharmD, BCPS, is a licensed pharmacist with more than 13 years of experience across retail pharmacy, clinical pharmacy, medication safety, pharmacy program development, and healthcare administration. He is the founder of HelloPharmacist.com, where he helps patients...
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