TONGKAT ALI SIDE EFFECTS: WHAT YOU SHOULD KNOW
Tongkat Ali, also known as Eurycoma longifolia, is a tree native to Southeast Asia, its leaves and other parts have been used for centuries by traditional medicine practitioners to treat a wide range of problems, including low testosterone, due to their many potential beneficial properties. However, like any natural preparation or medicine, Tongkat Ali extract can cause side effects, so it's important to understand the potential risks before taking any new supplement, including Tongkat Ali:
Adverse Effects, Precautions and Contraindications
Tongkat Ali, is generally considered safe when used at recommended levels, but caution is advised  for individuals with certain health conditions and those using specific medications. This herbal remedy, while offering various health benefits, has associated risks including potential adverse effects like insomnia, anxiety, and restlessness, and should be avoided by those with allergies to its constituents or to members of the Simaroubaceae family.
Read more about what Tongkat Ali is here.
Avoid having known allergy or hypersensitivity to Eurycoma longifolia, its constituents, or members of the Simaroubaceae family.
- General. There is little information available on the adverse effects associated with Eurycoma longifolia. According to secondary sources, reported side effects include insomnia, anxiety, and restlessness.
- Musculoskeletal. According to secondary sources, reported side effects include restlessness.
- Neurologic/CNS. According to secondary sources, reported side effects include insomnia.
- Psychiatric. According to secondary sources, reported side effects include anxiety.
- Use cautiously in patients using hypoglycemic agents, based on studies in animals suggesting that Eurycoma longifolia reduced blood glucose in hyperglycemic animals (Husen et al., 2004) and unpublished studies in humans suggesting the possibility for increased blood glucose.
- Use cautiously in people with weakened immune systems, as some evidence suggests that it may further weaken immune function, according to secondary sources.
- Use cautiously in individuals using propranolol as, in healthy males, a water-based extract of Eurycoma longifolia decreased the bioavailability (by absorption) of propranolol (Salman et al., 2010).
- Avoid in men with breast cancer or prostate cancer, diabetes mellitus, heart disease, kidney disease, liver disease, or sleep apnea, according to secondary sources.
- Avoid in children and pregnant and lactating women, due to a lack of sufficient safety data.
- Avoid in patients with known allergy or hypersensitivity to Eurycoma longifolia, its constituents, or members of the Simaroubaceae family.
Pregnancy and Lactation
- Not suggested due to lack of sufficient data.
- Information on Eurycoma longifolia’s effects on lactation is lacking in the National Institute of Health’s Lactation and Toxicology Database (LactMed).
Brief Safety Summary
- Possibly safe: When used at commonly suggested levels, based on history of use. There is little information available on adverse effects associated with Eurycoma longifolia.
- Possibly unsafe: When used in patients using hypoglycemic agents (Husen, Pihie, & Nallappan, 2004). When used in people with weakened immune systems. (according to secondary sources). When used in individuals using propranolol (Salman et al., 2010).
- Likely unsafe: When used in men with breast cancer or prostate cancer, diabetes mellitus, heart disease, kidney disease, liver disease, or sleep apnea, according to secondary sources. When used in children or pregnant or lactating women, due to a lack of sufficient safety data. When used in patients with known allergy or hypersensitivity to Eurycoma longifolia, its constituents, or members of the Simaroubaceae family.
Safety and Toxicity
Key findings  on various studies on the safety and toxicity of E. longifolia (Tongkat Ali), a traditional Malaysian herbal medicine:
- Safe Dosage: Therapeutic concentrations (2.5 µg·mL−1) are generally safe for human spermatozoa in vitro. However, higher concentrations (over 100 µg·mL−1) may be cytotoxic. For more information on dosing, see the blog post Dosage of Tongkat Ali.
- Animal Studies: No negative effects were observed on offspring in terms of malformations, body weight, or number. The alcoholic extract's oral lethal dose 50 (LD50) in mice is 1500–2000 mg/kg, and the aqueous extract's LD50 is over 3000 mg/kg.
- Toxicity in Different Extracts: The water-based fraction is the safest, with a higher LD50 (>3000 mg/kg) than other fractions.
- Physta® Extract Study: Using male and female Wistar rats, no significant changes were observed in blood chemistry, histopathology, or behavior even at high doses.
- Prostate Cancer Risk: While E. longifolia extract increases serum testosterone, it may pose a risk in elderly men for prostate problems. However, a study showed no significant change in serum prostate-specific antigen (PSA) levels.
- Safe Intake Level: The acceptable daily intake (ADI) for E. longifolia extract is up to 1.2 g/adult/day. Regular use at low doses seems safe for the pancreas.
- Reproductive Safety: In studies, no toxic symptoms were observed in pregnant rats, and a 100 mg/kg daily dose was considered safe.
- Liver and Kidney Safety: A study with a 400 mg/day dosage for 6 weeks showed no significant changes in liver and renal functions.
- Recommended Human Dose: The recommended dosage for men is 200–400 mg daily. It is commercially sold in tablet form.
- Precautions and Contraindications: E. longifolia should be used cautiously in patients with conditions like diabetes, weakened immune systems, and certain cancers. It is not recommended during pregnancy, lactation, for children, or for those with allergies to its constituents.
- Effect on Offspring: Studies in animals did not find any negative impact on offspring.
Does Tongkat Ali Make Your Body Stop Producing Testosterone?
It is very important to distinguish between anabolic steroids or synthetic testosterone and natural supplements such as Tongkat Ali. The introduction of synthetic testosterone or anabolic steroids into the body can suppress the body's natural production of testosterone. This is because when testosterone is supplied to the body from an external source, the body often reduces or stops its own production of the hormone. When individuals stop taking steroids or exogenous testosterone, testosterone levels may decrease for a period of time until the body's natural production mechanism is reactivated or restored. You can read more about the male hormone testosterone here.
In contrast, the effects of tongkat ali in restoring normal testosterone levels appear to be less due to actually “stimulating” testosterone synthesis, but rather by increasing the release rate of “free” testosterone from its binding hormone, sex-hormone-binding-globulin (SHBG). In this way, Eurycoma may be considered not so much a testosterone “booster” (such as an anabolic steroid), but rather a “maintainer” of normal testosterone levels and a “restorer” of normal testosterone levels (from “low” back “up” to normal ranges). This would make Eurycoma particularly beneficial for individuals with sub-normal testosterone levels, including those who are dieting for weight loss, middle-aged individuals suffering with fatigue or depression, and intensely training athletes who may be at risk for overtraining .
Also, in accordance with one study, Eurycomanone (the highest concentrated quassinoid in the root extract of E. longifolia) enhanced testosterone steroidogenesis at the Leydig cells by inhibiting aromatase conversion of testosterone to estrogen .
In accordance with one study Pharmacologically increased levels of cortisol have a significant negative effect on circulating testosterone .
Is Tongkat Ali Bad for the Kidneys?
As with all supplements, excessive use or use by individuals with medical conditions can pose a risk.
One of the concerns with herbal supplements, including Tongkat Ali, is the possible adulteration or use of impurities in supplements. Some products marketed as Tongkat Ali may contain other ingredients or contaminants that may be harmful, including substances that may affect kidney function. It is very important to make sure that you are getting a pure, high quality product from a reputable source.
It is always possible that individual sensitivities or allergic reactions may cause adverse effects, including on the kidneys.
Like many herbal supplements, Tongkat Ali may interact with medications or other supplements. These interactions may have unintended effects, including effects on the kidneys.
Is Tongkat Ali Safe for the Heart?
There is little direct evidence that Tongkat Ali has harmful effects on the heart when taken at recommended doses. Some studies suggest that it may have antioxidant properties and other beneficial properties that may benefit cardiovascular health. For more information on the potential benefits of Tongkat Ali, see the blog post Tongkat Ali benefits.
As Tongkat Ali can increase energy levels, there may be concerns about its possible stimulant effects and its effects on blood pressure and heart rate. So far, there is no strong evidence that Tongkat Ali has a significant negative effect on blood pressure. However, individual reactions may vary.
One of the important risks of herbal supplements, including Tongkat Ali, is possible adulteration. Some supplements marketed as Tongkat Ali may contain contaminants or other ingredients that can affect the heart. It is therefore very important to purchase a pure, high quality product from a reputable manufacturer.
As with any supplement or medicine, the effects of interactions with other medicines are possible. For example, if a person is taking heart medication, there may be interactions that can affect heart function or blood pressure. Particular caution should be exercised by individuals who already have heart problems. Even if a substance is generally considered safe for the general population, it may pose a risk to a person with heart disease.
The usage is authorized but must be under medical supervision as their interaction with certain drugs, such as Sildenafil (Viagra), tadalafil (cialis) and vardenafil and other synthetic PDE-5i drugs, can cause negative effects. Patients suffering from cardiovascular diseases such as hypertension, atherosclerosis are mostly treated with drugs containing nitrates, consequently combining such drugs with synthetic PDE-5i may drastically lower their blood pressure (Stief et al. 1998). Therefore, the unknowing consumption of such HMPs that contain undeclared synthetic PDE-5i may pose a serious health threat to the patient .
In accordance with a meta-analysis (2021) of 9 studies Only one clinical study reported adverse effects associated with E. longifolia treatment, which included gastrointestinal symptoms and itching, while in another study it had adverse events in both treated and placebo groups .
Eu Regulation Safety of Eurycoma longifolia (Tongkat Ali) root extract as a novel food pursuant to Regulation (EU) 2015/2283 says that in EU safety of the Tongkat Ali has not been established under any condition of use. In high doses it has the potential to induce DNA damage, which is of concern, particularly locally for tissues that represent first sites of contact .
Important to know
Although the side effects of Tongkat Ali are extremely rare, it is still important to be aware of possible risk factors. If you notice any side effects, you should stop taking Tongkat Ali and consult a healthcare professional.
You should always consult your doctor before taking any new supplement (including Tongkat Ali) - especially if you are taking other medicines, have a chronic condition or are pregnant or breastfeeding. A healthcare professional can help you understand how Tongkat Ali may affect you and whether it is safe for your specific health needs.
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