Bhunimba (Kalmegh): Benefits, Evidence, Dosage & Safety

TL;DR

Bhunimba (kalmegh, Andrographis paniculata) is the bitter Ayurvedic herb for coughs and colds. A 2017 meta-analysis of 33 RCTs found modest improvements in cough and sore throat versus placebo, though the trials were poor quality. One 1991 RCT found 6 g/day roughly matched paracetamol for sore throat on day 3.

What it is

Bhunimba is an Ayurvedic name for Andrographis paniculata (Burm.f.) Nees, an intensely bitter herb of the Acanthaceae family widely known as kalmegh or the "king of bitters" (Herbal Reality monograph; Nature study). In Ayurvedic materia medica it is also known as bhunimba, "neem of the earth," for its bitter, neem-like taste and effects (same monograph). Its major bioactive constituent is andrographolide (evidence review).

Traditional use

Andrographis paniculata has traditionally been used in Indian and Chinese herbal medicine for cough, cold, and influenza (Hu et al. 2017, PLOS ONE), and in Ayurveda as a bitter tonic and general stomach remedy (Herbal Reality monograph). Tradition is not clinical proof. The trial evidence gets its own section below.

What modern research says

Acute respiratory tract infections (cough, sore throat, common cold)

The largest synthesis is a 2017 systematic review and meta-analysis in PLOS ONE covering 33 randomized controlled trials with 7,175 patients (Hu et al. 2017). Compared with placebo, A. paniculata improved cough (596 patients; standardized mean difference −0.39, 95% CI −0.67 to −0.10) and sore throat (314 patients; SMD −1.13, 95% CI −1.37 to −0.89). It also shortened the duration of cough, sore throat, and sick leave/time to recovery compared with usual care. No major adverse events were reported; minor ones were mainly gastrointestinal. The authors' own caveat is the part I keep coming back to: the methodological quality of the included trials was overall poor, most trials used commercial products with seldom-reported manufacturing or quality-control details, and heterogeneity was substantial (Hu et al. 2017).

An earlier, smaller meta-analysis (4 trials; 433 patients across the 3 trials that entered the analysis) reached a similar conclusion: A. paniculata alone or in a fixed combination with Acanthopanax senticosus was more effective than placebo for uncomplicated upper respiratory tract infection, with a 10.85-point difference favoring the herb on the symptom-severity score (95% CI 10.36–11.34, P < 0.0001) (Poolsup et al., Journal of Clinical Pharmacy and Therapeutics).

Pharyngotonsillitis (sore throat with fever)

In a 1991 randomized, double-blind trial, 152 Thai adults with pharyngotonsillitis received paracetamol, 3 g/day of A. paniculata, or 6 g/day of A. paniculata for 7 days. The high dose was comparable to paracetamol, and significantly better than the low dose, for relief of fever and sore throat at day 3; by day 7 the groups no longer differed. Minimal, self-limiting side effects occurred in about 20% of each group (Thamlikitkul et al., J Med Assoc Thai). One old trial. Interesting, not practice-changing.

Common cold (standardized extract)

A double-blind, placebo-controlled trial of the standardized extract SHA-10 found it reduced the intensity of tiredness, sleeplessness, and sore throat versus placebo in a duration-dependent manner, with 4 days of treatment outperforming 2 days (Cáceres et al., reviewed in).

Limitations of the evidence

The signal is consistent across reviews, but the foundation is weak: small, often poorly reported trials, frequent use of combination products, and little standardization of extracts. Nothing here establishes A. paniculata as a substitute for medical care of respiratory infections, and well-designed trials are still needed (Hu et al. 2017).

Dosage

There is no standardized human dose. The trials used widely different preparations, most poorly described. The one well-specified trial (Thamlikitkul 1991) used 6 g/day of powdered herb for 7 days (PubMed). Commercial extracts (e.g., SHA-10, KalmCold) were standardized to andrographolide content rather than crude weight, so gram doses of raw powder and extract doses are not interchangeable. Do not self-prescribe based on these figures.

Safety & contraindications

The meta-analysis found no major adverse events, with minor ones mainly gastrointestinal (Hu et al. 2017). That reassurance has limits, and they matter. Case reports of anaphylaxis or anaphylactic shock after Andrographis products exist, along with reports of elevated liver enzymes (AST/ALT) in some users (Scientific Reports study). Australia's TGA has issued a formal safety advisory: andrographis may cause sudden, potentially life-threatening allergic reactions, including in people who previously used it without any reaction, and by 31 December 2025 the TGA had received 287 anaphylaxis reports linked to andrographis medicines, including one fatal case in 2024 (TGA safety advisory). On 17 September 2026 the TGA removed Andrographis paniculata from the Permissible Ingredients Determination, meaning it can no longer be used in new listed medicines in Australia. Most of those reports involved multi-ingredient products, which complicates attribution, but the signal is real.

Avoid Andrographis during pregnancy: animal studies show antifertility effects, and abortifacient effects have been documented in drug references (Drugs.com monograph). Talk to a clinician before use if you take prescription medicines or have an ongoing medical condition. Stop use and seek care immediately for any sign of allergic reaction (rash, swelling, breathing difficulty).

FAQs

Does kalmegh help with colds and cough?

Possibly, but the evidence is weak. A 2017 meta-analysis of 33 RCTs found it improved cough and sore throat and shortened illness compared with placebo, but the trials were of poor quality (Hu et al. 2017). It is not a cure and not a substitute for medical care.

Is it as effective as paracetamol for sore throat?

In one 1991 trial, 6 g/day of A. paniculata relieved fever and sore throat about as well as paracetamol at day 3 in adults with pharyngotonsillitis. By day 7 there was no difference between groups (Thamlikitkul et al.). This is a single old trial, not a basis for replacing paracetamol.

How quickly does it work?

In the trials, symptom improvements were measured over days, not hours. The SHA-10 cold trial found 4 days of treatment worked better than 2 (reviewed in). It is not an instant remedy.

Is kalmegh safe?

Short courses in trials were generally well tolerated with mostly mild stomach upset (Hu et al. 2017). However, severe allergic reactions including anaphylaxis have been reported, and some users showed elevated liver enzymes (Scientific Reports study). Anyone with a history of allergies should be especially cautious.

Can I take it while pregnant or breastfeeding?

Avoid it. Animal data show antifertility effects, and drug references document abortifacient effects (Drugs.com monograph).

Can kalmegh prevent or treat COVID-19?

No established role. One double-blind randomized trial (165 asymptomatic or mildly symptomatic COVID-19 patients; Andrographis extract providing 180 mg andrographolide daily for 5 days vs placebo) found no reduction in COVID-19 progression overall. Only faster relief of headache and loss of smell, with mild diarrhea as the main side effect (Kanokkangsadal et al. 2023). Follow public-health guidance for COVID-19.

Sources

Disclaimer

This article is for educational purposes only and is not medical advice. Herbal products can interact with medications and are not suitable for everyone. Talk to a qualified healthcare practitioner before use, especially if you are pregnant, breastfeeding, managing a medical condition, or taking prescription medicines.