Wohlmuth H. Andrographis for the common cold Botanical Pathways. 2001; 10:6-8.Andrographis (Andrographis paniculata) is traditionally used in Indian, Chinese, and Korean medicine and is now being used in western herbal medicine. Andrographis is a tall shrub and is part of the family Acanthaceae. It has been used to treat a number of conditions including fever, pneumonia, stomach conditions, bronchitis, and diabetes. The active ingredients are a family of compounds known as andrographolides, which are diterpenoid lactones. The lactone considered to be the main active is bitter and is found in high concentrations (2%) in the leaves of the plant.
Clinical studies have investigated the use of andrographis in tonsillitis and the common cold. One study compared andrographis at two doses (1 g or 2 g 3 times a day, containing at least 6% total lactones) with paracetamol (acetaminophen, 1,300 mg three times a day) in patients with tonsillitis. Both fever and sore throat significantly decreased in the high dose andrographis and paracetamol groups, but not in the low-dose andrographis group. Three other studies looked at the use of andrographis to treat the common cold. They used doses of 1,020 -1,200 mg per day of a standardized extract (from Swedish Herbal Institute, Gothenburg, Sweden) and reported significant improvements in shivering, sore throat, and achiness; the number of sick leave days was significantly lowered as well. Self-assessments showed patients felt the course of the cold was easier and full recovery was faster compared to placebo. The largest study (158 patients) showed a very significant reduction in the severity of tiredness, earache, sleep disturbance, sore throat, and nasal secretions after two days of treatment compared to placebo. A double-blind, placebo-controlled study showed that use of andrographis also had a significant preventative effect, lowering the incidence of common cold 32% when taken 5 times a week in the winter months. The mechanism by which andrographis confers these effects is not fully elucidated, but it seems likely that it is due to immunostimulation rather than antimicrobial activity.
Andrographis also has a number of specific physiological effects. It has been shown to have antiinflammatory properties, possibly through the prenvention of monocyte adhesion, as shown in animal studies. Additional animal studies have shown that it protects the liver from toxins, including paracetamol overdose. It also increases bile volume. Aqueous extracts of the herb lowered blood pressure in rats, possibly mediated through activating the potent vasodilator nitric oxide. The active ingredient, andrographolide, inhibited platelet aggregation in human platelets. Antimalarial and antiviral (HIV) activity has also been shown both in vitro and in vivo.
Safety studies and clinical trials have not reported any toxic effects, but contraceptive and abortifacient effects in mice and rabbits have led to a recommendation that pregnant women and women trying to conceive not use the herb. According to the author, dosage levels used in clinical studies have been relatively high, in the range of 1,200 mg of the dried herb, to compensate for its relatively low concentration or andrographolide (5%). The recommended daily dose of andrographolide is 45-60 mg. A standardized extract concentrated to 30-40% is also available and may be a more manageable dosage form.
Risa N. Schulman, Ph.D.