Tongkat ali: Ali et al., 2025
A 71-year-old man developed atrial flutter four days after starting tongkat ali, with normal thyroid, electrolytes, and cardiac structure. This is a single case report, the lowest tier of clinical evidence, useful as a flag for surveillance, not as proof of causation.
Key takeaways
- One 71-year-old man developed atrial flutter within days of starting tongkat ali supplementation, with no other identifiable triggers.
- The authors ruled out standard arrhythmia causes: thyroid dysfunction, electrolyte imbalance, and structural heart disease.
- This is a case report, a single patient observation, which cannot establish causation, only temporal association.
- No rechallenge was performed, so we don't know if stopping and restarting the supplement reproduced the arrhythmia.
- The product source and dose were not specified, and no third-party testing confirmed the ingredient profile.
The study
Ali (2025, Cureus) reports a single 71-year-old male who presented with four days of palpitations and dizziness after initiating tongkat ali supplementation. Electrocardiogram showed supraventricular tachycardia at 130 bpm, confirmed as atrial flutter after adenosine administration. Workup included thyroid function tests, electrolytes, and cardiac imaging, all normal. The patient had no prior history of arrhythmia and no concurrent medications or supplements. The authors note this as the first documented case linking tongkat ali to atrial flutter. The paper does not specify the dose, brand, duration of use prior to symptom onset, or whether the supplement was third-party tested. The patient's arrhythmia resolved, but no rechallenge was performed. The case is presented as a probable adverse event based on temporal association and exclusion of other causes.
How to read this study
What this paper does well: The authors performed the standard arrhythmia workup competently. They ruled out thyroid dysfunction, electrolyte imbalances, and structural heart disease, the three most common reversible triggers for new-onset atrial flutter. That is the correct differential. They also documented the temporal relationship clearly: symptoms began within days of supplement initiation. The patient had no prior arrhythmia history and no concurrent supplements or medications that could confound the picture. That exclusion work is solid.
What this paper is missing: No rechallenge. A rechallenge means stopping the supplement, observing resolution, then reintroducing it to see if the arrhythmia returns. Without that, the temporal association is suggestive but not conclusive. The paper also doesn't specify dose, brand, or third-party testing results, critical gaps when evaluating supplement-related adverse events, since contamination and adulteration are real risks in unregulated products. We don't know if this was tongkat ali itself or something else in the capsule.
How I weight this paper: I treat this as a flag worth tracking, not a reason to conclude tongkat ali causes arrhythmia. A case report is hypothesis-generating. It says "pay attention to this pattern", it does not prove causation. If five more case reports surface, or if a cohort study shows elevated arrhythmia incidence in tongkat ali users, the signal strengthens. Right now, it's a single 71-year-old man with one event. I file it, I watch for replication, and I don't overweight it.
What they found
The patient presented with sustained supraventricular tachycardia at 130 beats per minute. Adenosine administration revealed atrial flutter with 2:1 atrioventricular conduction. Thyroid-stimulating hormone, free T4, and electrolytes (sodium, potassium, magnesium) were within normal limits. Echocardiography showed normal left ventricular function and no structural abnormalities. The patient denied alcohol use, stimulant medications, or other supplements. The arrhythmia resolved with standard management, and the patient discontinued tongkat ali. No follow-up rechallenge was conducted. The authors conclude the arrhythmia was "Tongkat Ali-induced" based on temporal association and absence of alternative explanations. They note this is the first case in the published literature linking tongkat ali to atrial flutter.
What it means for the average man
If you are under 60 with no cardiac history, this case report does not change the risk-benefit calculation for tongkat ali supplementation. Atrial flutter is rare in younger populations, and a single case in a 71-year-old is not generalizable. That said, if you develop new palpitations, chest discomfort, or dizziness after starting any supplement, tongkat ali or otherwise, stop the supplement and see a physician. Temporal association is a valid reason for clinical caution even when causation isn't proven. For men over 65 or with existing cardiac conditions, discuss supplement use with your cardiologist before starting. The absence of dose and brand information in this report also reinforces the importance of third-party tested products. Unknown contaminants pose more risk than known ingredients.
The caveats
This is a single case report, the lowest tier of clinical evidence. It cannot establish causation, only raise a hypothesis. The patient was 71, an age group with elevated baseline arrhythmia risk. The paper does not disclose the dose, duration, or brand of tongkat ali, nor whether the product was third-party tested. Without rechallenge, we cannot confirm the supplement caused the arrhythmia. The mechanism by which tongkat ali might trigger atrial flutter is also unexplained. The authors speculate but provide no pharmacological pathway. No prior trials or case reports have linked tongkat ali to arrhythmia, so this is an isolated signal. Industry-funded trials of tongkat ali have not reported arrhythmia as an adverse event, though those trials typically exclude older adults with cardiac risk factors.
Frequently asked questions
Should I trust a single case report?
No, not as proof. A case report documents one patient's experience, it generates a hypothesis but cannot prove causation. Case reports are valuable for rare adverse events that would never show up in trials, but they need replication. If ten case reports surface with the same pattern, the signal strengthens. One case is a flag, not a verdict.
What is rechallenge and why does it matter?
Rechallenge means stopping the suspected agent, confirming symptom resolution, then reintroducing it to see if the symptom returns. It's the closest you can get to causation in a single patient. Without rechallenge, temporal association is suggestive but not conclusive, correlation is not causation.
Does this mean tongkat ali is unsafe?
No. This is one 71-year-old man with one event. Tens of thousands of men use tongkat ali without arrhythmia. The question is whether tongkat ali increases arrhythmia risk at the population level, that requires cohort studies or trial data, not a single case. Right now, this is a signal to monitor, not a reason to avoid the supplement.
What should I do if I develop palpitations on tongkat ali?
Stop the supplement immediately and see a physician. Even if causation isn't proven, temporal association is a valid reason for clinical caution. Your doctor will rule out thyroid, electrolytes, and structural heart disease, the same workup this case report describes. If everything else is clear and symptoms resolve off the supplement, you've done your own dechallenge.
Sources
- Ali M. Tongkat Ali-Induced Atrial Flutter: A Probable Case. Cureus. 2025. PubMed.
- Hendriks T, et al. The effect of Eurycoma longifolia on testosterone levels: A systematic review and meta-analysis. Complement Ther Med. 2021.
These statements have not been evaluated by the Food and Drug Administration. This article is for educational purposes only and is not intended as medical advice. Consult a healthcare provider before starting any supplement regimen, particularly if you have existing cardiac conditions or are taking medications.
