Bulbine Natalensis: Benefits, Side Effects and Dosage

Bulbine natalensis, a succulent indigenous to southern Africa, has gained popularity for its traditional use in supporting male vitality and sexual health. In recent years, scientific research has begun to validate some of the plant’s purported benefits, while also highlighting important safety considerations. This comprehensive guide explores the evidence-backed benefits, potential side effects, and recommended dosages of Bulbine natalensis, helping you make informed decisions about its use.

Benefits of Bulbine Natalensis

Bulbine natalensis is more than just a folk remedy. Modern studies have examined its effects on sexual function, wound healing, inflammation, and more. Let’s explore these potential health benefits.

Benefit	Description	Evidence Strength	Sources
Libido & Sexual Health	Enhances libido, sexual performance, and reproductive hormones, especially in males	Strong (animal studies, preliminary human trial)	1 8 10 9
Wound Healing	Promotes faster wound contraction and stronger tissue repair	Moderate (animal studies)	3 4
Anti-inflammatory	Reduces inflammation, relevant to skin health and wounds	Moderate (in vitro)	3
Antioxidant	Scavenges free radicals, supports cellular health	Moderate (in vitro)	3 5
Antifungal	Inhibits certain fungi, supports skin remedy uses	Limited (in vitro)	2
Blood Clotting	May reduce platelet aggregation, supporting cardiovascular health	Limited (in vitro)	5

Table 1: Main Benefits of Bulbine Natalensis

Sexual Health and Reproductive Function

One of the most well-researched benefits of Bulbine natalensis is its effect on male sexual health. Animal studies demonstrate that low to moderate doses of Bulbine natalensis extract (25–50 mg/kg) significantly enhance libido, increase testosterone and luteinizing hormone levels, and improve sexual performance in male rats. These doses also increased mating and fertility indices, supporting its reputation as a prosexual agent 1 8 10. Notably, these effects were not seen at higher doses (100 mg/kg), where some parameters worsened—a critical point for safety.

A short-term, double-blind clinical trial in healthy men found no serious adverse effects with a commercial Bulbine natalensis supplement, adding preliminary human support to its safety and potential efficacy for sexual health 9.

Wound Healing and Dermatological Benefits

Traditional healers in southern Africa have long used Bulbine natalensis as a topical remedy for wounds and skin conditions. Research supports this practice: topical application of Bulbine natalensis gel accelerated wound contraction, increased collagen production, and improved tensile strength in animal models 3 4. These findings suggest the plant’s usefulness in promoting tissue repair and may justify further development of affordable wound care products.

Anti-inflammatory and Antioxidant Properties

Bulbine natalensis contains a range of phytochemicals—including saponins, alkaloids, and phytosterols—that contribute to its antioxidant and anti-inflammatory effects 3 5. Laboratory assays show that extracts can inhibit inflammatory markers and scavenge free radicals, both of which are important in protecting cells from damage and supporting overall health.

Antifungal and Antibacterial Activity

Extracts of Bulbine natalensis have demonstrated activity against certain fungal pathogens, notably Aspergillus flavus, which is relevant to its traditional use for skin complaints. The antifungal effect is attributed to phytosterols present in the plant, though the overall activity is considered moderate and more research is needed 2.

Cardiovascular Support

Bulbine natalensis extracts have exhibited anti-platelet aggregation properties in vitro, suggesting a potential role in reducing the risk of blood-clotting-related diseases. However, these findings are preliminary and based on laboratory studies rather than clinical trials 5.

Side Effects of Bulbine Natalensis

While Bulbine natalensis offers several promising health benefits, it is equally important to address its safety profile. Most evidence comes from animal studies, with limited short-term human data.

Side Effect	Description	Severity	Sources
Liver & Kidney Effects	Altered liver/kidney function markers, mild tissue changes	Moderate (animal studies)	6 7
Blood Lipid Changes	Increased cholesterol and triglycerides, decreased HDL	Moderate (animal studies)	6
White Blood Cell Changes	Increased WBC count, changes in immune cell proportions	Moderate (animal studies)	6
Reproductive Toxicity (High Dose)	Reduced testosterone and progesterone at high doses, increased fetal resorption	Serious (high doses)	8 10
Minor Short-term Effects (Humans)	Marginal changes in alkaline phosphatase and creatinine	Mild (short-term, human)	9

Table 2: Key Side Effects of Bulbine Natalensis

Liver and Kidney Health

Repeated oral administration of Bulbine natalensis extract in animal studies, especially at moderate to high doses (50–100 mg/kg), led to significant changes in liver and kidney function markers. These included increased liver enzymes (ALT, AST, GGT, ALP), higher total bilirubin and urea, and mild structural changes in the liver and kidney tissues 7. While no acute toxicity was observed, these findings indicate a risk of organ stress with long-term use or at higher dosages.

Blood Lipid and Hematological Changes

Bulbine natalensis extract caused notable shifts in lipid profiles in rats: increased cholesterol and triglycerides, decreased HDL (“good”) cholesterol, and a higher atherogenic index, potentially raising the risk of atherosclerosis if used long-term 6. Additionally, the extract affected white blood cell counts, with increases in overall WBC and changes in immune cell subtypes. While these effects were not acutely dangerous, they suggest possible immune modulation and cardiovascular risk.

Reproductive Toxicity at High Doses

At standard doses (25–50 mg/kg), Bulbine natalensis appears to be safe and even beneficial for male reproductive health. However, at higher doses (100 mg/kg), studies reported reduced testosterone and progesterone, negative effects on fertility, and increased fetal resorption in female rats 8 10. This dose-dependent toxicity underscores the importance of adhering to recommended dosages.

Human Safety Data

A short-term (28-day) clinical trial in healthy men found only minor, clinically irrelevant changes in blood chemistry after daily supplementation with a commercial Bulbine natalensis product 9. While reassuring, this study was limited in duration and sample size, and does not rule out long-term or cumulative risks.

Other Considerations

• Cytotoxicity: Extracts showed little cytotoxic effect in basic laboratory tests 5.
• Topical Use: No adverse effects reported for topical application on wounds in animal models 4.

Dosage of Bulbine Natalensis

Determining the right dosage is crucial to maximizing benefits and minimizing risks. Most data come from animal research, with limited human studies.

Formulation	Typical Dose (Animal)	Human Equivalent (Est.)	Notes & Sources
Oral Extract	25–50 mg/kg (rat)	~200–400 mg/day (70 kg adult)*	Effective and safe range in studies 1 6 8 10
High Dose	100 mg/kg (rat)	~800 mg/day (70 kg adult)*	Associated with toxicity 6 8 10
Commercial Capsule	650 mg/day (2 x 325 mg)	650 mg/day	Used in human trial 9
Topical Gel	N/A (applied as gel)	N/A	Effective for wound healing 4

*Table 3: Common Dosages of Bulbine Natalensis
*Human equivalent doses are estimated using standard body surface area conversion from animal studies.

Oral Dosage

• Animal Studies: Most research used 25–50 mg/kg of aqueous extract in rats, which translates to roughly 200–400 mg daily for an average adult human after appropriate scaling 1 8 10.
• Human Trials: A commercial supplement (ProLensis™) used 650 mg daily in two divided doses, which was well-tolerated over 28 days 9.

Caution: Doses above 50 mg/kg (rat) or the equivalent of ~400–650 mg/day in humans were associated with negative effects in animal studies, particularly on liver, kidney, and reproductive health 6 7 8 10.

Topical Dosage

For skin and wound healing, Bulbine natalensis is used as a gel applied directly to the affected area. Animal studies support its safety and efficacy in this form, but specific concentration details are often lacking 3 4.

Duration of Use

• Most studies investigated effects over 7–14 days in animals, or up to 28 days in humans 1 6 9.
• Long-term safety is unknown, so use should be limited unless more data become available.

Practical Recommendations

• Start with the lowest effective dose and monitor for any side effects.
• Avoid high doses (>650 mg/day in adults) due to potential toxicity.
• Consult a healthcare provider before starting Bulbine natalensis, especially if you have pre-existing liver, kidney, or cardiovascular conditions.
• Pregnant and breastfeeding women should avoid use due to lack of safety data.

Conclusion

Bulbine natalensis is a promising herbal remedy with a rich tradition in southern African medicine and growing scientific support for its benefits. Key takeaways from the current evidence include:

• Effective for sexual health: Especially in males, at low to moderate doses, with support from animal and preliminary human studies.
• Promotes wound healing: Topical use accelerates tissue repair and collagen formation.
• Offers antioxidant, anti-inflammatory, and antifungal benefits: Relevant to both internal and skin health.
• Safety is dose-dependent: Low to moderate doses appear safe in the short term, but higher doses and long-term use carry risks, especially for liver, kidney, and reproductive health.
• Human data is limited: Most evidence comes from animal models, with only one short-term human trial to date.

In summary:

• Bulbine natalensis may support sexual health, wound healing, and more.
• Adhere strictly to recommended dosages.
• Monitor for side effects, especially if using orally.
• Consult a healthcare provider before use.
• More research is needed, particularly for long-term human safety.

By balancing tradition with science, Bulbine natalensis can be a valuable addition to natural health regimens—when used responsibly and with respect for its potent bioactive properties.