From Ergo Log
Andrographolide, the main active substance in the Asian plant Andrographis paniculata, boosts testosterone levels and improves sexual performance. Pharmacologists at Khon Kaen University draw this conclusion from tests they did on male mice.
In the Indian Pharmacopoeia there are 26 Ayurvedic preparations in which extracts of Andrographis paniculata are prominent ingredients. This is because andrographolide, probably the most important bioactive substance in Andrographis paniculata, is amazingly versatile. Researchers think that andrographolide and its natural and synthetic analogues are interesting candidates for medicines against diseases such as asthma, diabetes, stroke or arthritis, and can help inhibit inflammation, tumours and viruses. [Evid Based Complement Alternat Med. 2013;2013:846740.]
Armenian researchers have wondered whether Andrographis paniculata may contain substances that affect men's fertility. In a Phase-1 trial researchers found no effects, but did notice that their subjects had an increased interest in sex. [Phytomedicine. 2005 Jun;12(6-7):403-9.]
The combined testosterone and sildenafil effect of Andrographis paniculata
The Thai pharmacologists' study built on the Armenian's work. They gave male mice an oral dose of 50 mg andrographolide and put them in a cage with sexually receptive females. A control group were given sildenafil, the active ingredient in Viagra. The researchers recorded when and how often the male mice mounted the females, and discovered that andrographolide had a greater sex stimulatory effect than sildenafil – two hours after intake at least.
In-vitro experiments on blood vessels showed that andrographolide had a widening effect on these. The compound blocked narrowing of the blood vessels through noradrenalin. Going on previous studies, the researchers think that andrographolide blocks the alpha-adreno receptors. [J Ethnopharmacol. 1997 Apr;56(2):97-101.]
An increase in sexual activity is likely to be linked to a raised testosterone level, so the researchers set up an animal study in which they examined specifically the effect of andrographolide on the testosterone level. The results of these were a little unusual. The study lasted eight weeks, and after the mice had been given 50 mg andrographolide every day for two weeks their testosterone levels had not changed. After four weeks there had been a sharp rise in the testosterone level, and after six weeks it had returned to normal.
A bit strange.
If you're thinking of experimenting with Andrographis paniculata, make sure you buy a concentrated product. Analyses show that gross extracts of Andrographis paniculata only contain several percent of andrographolides. [J Chromatogr Sci. 2008 Sep;46(8):747-50.]
The Thai researchers gave their mice 50 mg andrographolide per kg bodyweight. Converted to humans that would mean about 5 mg per kg bodyweight. So if you weight 80 kg you'll need at least 400 mg andrographolide a day. (To make it easier we're assuming that the chemical relatives of andrographolide all have roughly the same effect.)
The strongest Andrographis paniculata extract that we know contains about 50 percent andrographolides.
Andrographis paniculata extracts also inhibit blood clotting, by the way. [Eur J Pharmacol. 2006 Dec 28;553(1-3):39-45.] If you use anti-coagulants or produce few coagulant factors yourself you'd be wise to avoid Andrographis paniculata.
Food Chem Toxicol. 2010 Jul;48(7):1934-8.