Fadogia agrestis and tongkat ali: what the research shows

Fadogia agrestis has only been tested in animals. Tongkat ali has human trials, and a 2022 meta-analysis found higher testosterone in men who took it.

Nobody has tested the two together. So any claim that they work as a pair, or any cycling schedule for them, is a guess.

Does fadogia agrestis raise testosterone?

In rats, yes. In people, nobody knows.

Fadogia agrestis is a shrub from West Africa that people use traditionally for sexual function. A search of PubMed for the plant returns 10 records. They are animal studies, plant chemistry papers and market surveys. None is a human trial.

The study behind the testosterone claim used male rats. They got an aqueous stem extract at 18, 50 or 100 mg per kg of body weight for 5 days. Their blood testosterone rose, and so did their mounting and intromission counts (Yakubu et al., 2005).

A later rat study found the extract restored erectile markers in rats given the antidepressant paroxetine. Its authors recommended the extract only after clinical trials (Ogunro and Yakubu, 2022).

Rat results often don’t carry over to people.

Is fadogia agrestis safe?

Human safety is unknown, and the animal data raise flags.

• In a 28-day rat study at the same three doses, the extract changed several testicular enzymes and markers. The authors called the changes adverse effects on male rat testicular function. Some recovered after 10 days, mainly at the lowest dose (Yakubu et al., 2007).
• In another 28-day rat study, liver and kidney enzymes fell in the tissue and rose in the blood. The authors read this as damage to the cell membranes of liver and kidney cells (Yakubu et al., 2009).

There’s no human dose that has been shown safe or effective, so this page doesn’t give one.

Product quality is another problem. A lab analysis of 17 supplements sold as fadogia detected the phenolic compounds it measured in 12 of them. Five had none detectable (Avula et al., 2018).

Does tongkat ali raise testosterone?

It may, and the authors say you shouldn’t treat it as proven yet.

Tongkat ali is the root of Eurycoma longifolia, a Southeast Asian shrub. A 2022 systematic review covered nine studies. Five randomized trials went into the meta-analysis. Men taking tongkat ali had higher total testosterone than men on placebo (standardized mean difference 1.35, 95% CI 0.57 to 2.14). The result held in men with low testosterone.

The authors say it may be a safe and promising option, but that more research is needed before clinical use (Leisegang et al., 2022).

A higher number on a blood test is not the same as better sexual function or more muscle. The meta-analysis measured testosterone.

Can you take fadogia and tongkat ali together?

No study has tested the combination, so no one knows how it behaves.

You may see claims that the two are synergistic. No source backs that up. Since fadogia has no human safety data, stacking it with another hormone-active herb adds an unknown to an unknown.

Should you cycle fadogia and tongkat ali?

No study has tested a cycling schedule for either herb. Schedules like 5 days on and 2 off, or 3 weeks on and 1 week off, are guesses. Nothing shows your body “gets used to” these herbs.

Who should talk to a doctor first?

See a doctor before using either herb if:

• You have liver or kidney disease. Fadogia raised liver and kidney damage markers in rats.
• You want to have children. Fadogia changed testicular markers in rats.
• You take prescription medicine.
• You’re pregnant, breastfeeding or under 18.

If you have low testosterone symptoms, get your levels tested. A supplement can’t tell you what’s wrong.

See also our maral root guide.

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