Indian Journal of Traditional Knowledge
Vol. 10 (4), October 2011, pp. 668-671
A clinical study on the management of generalized anxiety disorder with
Vaca (Acorus calamus)
Bhattacharyya1* D, Sur1 TK, Lyle1 N, Jana2 U & Debnath2 PK
1Department of Pharmacology, Institute of Post Graduate Medical Education & Research, 244B,
Acharya J.C. Bose Road, Kolkata 700 020, West Bengal
2Research Unit, JB Roy State Ayurvedic Medical College & Hospital, Kolkata 700 004, West Bengal
Received 27.04.09; revised 13.04.10
In Ayurveda, Vaca (Acorus calamus, Family: Araceae), is reputed for its beneficial effects in various neurological
disorders. The present investigation was undertaken to evaluate the role of 70% hydro-ethanolic extract of Vaca or Acorus
calamus (ACE) on generalized anxiety disorder (GAD) in human. Hamilton’s Brief Psychiatric Rating Scale (BPRS) and
thorough clinical investigations were used to screen the subjects. Thirty-three participants (20 male and 13 female; average
age 36.2 yrs) were medicated with ACE in a fixed dose regime (500 mg/capsule, twice daily, p.o. after meal). They were
thoroughly investigated clinically and using standard questionnaires based on different psychological rating scale at baseline
(day 0), mid-term (day 30) and final (day 60). The scale also includes a number of direct queries about current levels of
experienced stress. Moreover, the questions are of a general nature and hence are relatively free of content specific to any
subpopulation group. The observations exhibited that, ACE not only significantly (p<0.001) attenuated anxiety related
disorders but it also significantly (p<0.001) reduced stress phenomenon and its correlated depression. ACE further
significantly (p<0.001) improved the willingness to adjustment. Therefore, it may be concluded that Vaca may be useful in
the treatment of GAD in human and may be a promising anxiolytic agent in near future.
Keywords: Anxiety disorders, Psychological stress, Depression, Vaca, Acorus calamus, Ayurvedic medicine
IPC Int. Cl.8: A01D 8/00, A01D 22/23, A01D 10/09, A01D 12/24, A01D 13/25, A01D 22/22, A01D 22/00
The facets of stress are essentially limitless; however,
broad categories include physical exertion, emotional
upset, persistent psychological pressure, existential
crisis and the residual effects of emotional trauma. It
has consistently been shown that individuals
experiencing stress have impaired physical and
mental functioning and increased use of healthcare
services1. The World Health Organization (WHO)
Global Burden of Disease Survey estimates that
mental disease, including stress-related disorders, will
be the second leading cause of disability by the year
20202. Current therapies for dealing with ‘stress’ are
extensive but perhaps not ideally targeted in most
cases. Pharmacological approaches are principally
focused on the treatment of depression and the
manifestations of both acute and chronic anxiety
disorders3. A potentially beneficial use of herbal
medicine involves the use of herbs as ‘adaptogens’ in
order to prevent stress-induced morbidity4. Ayurveda,
Indian system of traditional medicine has described
CNS-activity under Rasayana categories. Sushruta
describes Rasayana deals with the drugs and the
methods to maintain youth, to increase longevity,
intellectual capacity and strength as well as to enable
the patient to be freed from diseases5. A number of
medicinal plants from Ayurveda have been shown to
have activity by the traditional methods of
psychopharmacology, Vaca or Acorus calamus
(Family: Araceae), is one of them6. Acorus calamus
(AC) is a semiaquatic, perennial, aromatic herb with
creeping rhizomes. The plant is found in the northern
temperate and subtropical regions of Asia, North
America, and Europe. The plant exhibits polyploidy7.
The bioactive constituents so far identified are
asarones, shyobunones, acorones, octanoic acid, α-
cedrene, α-phellandrene, β-farnesene, γ-elemene,
etc.8. Many ethnomedicinal and ethnobotanical uses
have been ascribed to the rhizomes of the plant.
Moreover, pharmacological studies have revealed that
AC rhizome and its constituents α- and β- asarones,
BHATTACHARYYA et al.: VACA ON GENERALIZED ANXIETY DISORDER
wide range of pharmacological activities such as
sedative, CNS depressant, behavior modifying,
anticonvulsant, memory enhancing, antioxidant,
antiepileptic, etc8-11. Although the plant has been in
traditional use to treat neurological disorders for
thousands of years in India and China, but till date
there is no evidence-based clinical report. In this
context, we aimed to investigate the Rasayana plant,
Vaca (Acorus calamus) for its role in mental
disorders, especially Generalized Anxiety Disorders
(GAD) in human subject.
Rhizomes of Acorus calamus were washed, dried
and made into fine powder. This powder was soaked
in 70% hydro-ethanol. After 24 hrs at room
temperature, the materials were filtered under
vacuum. This process of extraction was further
repeated for three times. The combined alcoholic
extract of the plant was concentrated under reduced
pressure in a rotary evaporator. The concentrated
material was then lyophilized and the ultimate
product was filled in gelatin capsules (500 mg
equivalent weight)12. The product has been thorough
quality control testing and has demonstrated
consistent concentration of the plant extract. The
Programmed clinical trail was done in the Out-
Patient Clinics of the State Ayurvedic Medical
College & Hospital, Govt. of West Bengal, Kolkata.
The trial was conducted in accordance with good
clinical practice guidelines and conforming to the
declaration of Helsinki, following approval by the
Institutional Ethical Committee. Participants of both
sexes, of age group 18-60 yrs, suffering from GAD,
diagnosed during initial observation of the
participant and filling up of the Proforma for
detailed general examination of the participants and
Brief Psychiatric Rating Scale (BPRS)13 and in
whom the exclusion criteria were absent, were
included in this study, after getting their informed
written consent either in mother tongue (Bengali or
Hindi) or in English as the case may be. The
exclusion criteria of the study were hepatic and/or
renal disease, severe depression, organic lesion,
uncontrolled diabetic patient, and pregnant and
Participants judged eligible by the inclusion and
exclusion criteria were formally informed about the
study and those who gave written informed consent
were enrolled. The encapsulation contained 500 mg
of the plant extract (ACE) and was administered
orally in dose of one capsule, twice daily after meal.
Hence, each participant ingested two capsules per
day. The dose remained constant throughout the
study (i.e., no increase or decrease in dose). Any
concomitant illness and medication during study
period were recorded throughout the study. No other
anxiolytic medication including β-blockers anti-
depressants, etc. was permitted throughout the study.
The participants were followed-up at day 30 and
finally at day 60 from the starting of medication.
Study endpoints assessed and analyzed for each of
the participants consisted of both objective and
subjective measures. Primary outcome measures
consisted of subjective scores from five self reported
questionnaires including stress scale, anxiety scale,
depression scale, adjustment scale and attention
scale13-15. The questionnaires were chosen because
they have been validated and are widely accepted
amongst healthcare professionals. The scale also
includes a number of direct queries about current
levels of experienced stress. Moreover, the questions
are a general nature and hence are relatively free of
content specific to any subpopulation group. The
statistical analysis of the data was performed
according to by Chi-Square test and percentile
change compared to baseline results16.
Results and discussion
Stress is a risk factor for a number of diseases
and is an important predictor of health in general.
The physiology of stress has been well characterized
with an emphasis on the hypothalamic–pituitary–
adrenal (HPA) axis. It is well known that the
immune system and the nervous system are in
constant communication and are held in a subtle
balance that can be distorted by the impact of
stress1 7. Indian traditional medicine, Ayurveda has
based on a mind–body medicine approach with an
emphasis on relaxation techniques like yoga,
meditation and the use of ingested natural health
products to provide a pharmacological action in
order to provide an ‘adaptogenic’ or protective effect
In the study, Vaca was evaluated for its putative
adaptogenic action to negate anxiety, stress and
depression (Table 1). We enrolled 40 participants
for the period of 60 days. Thirty three participants
completed the trial (20 male, 13 female; average
age 36.2 yrs). Regarding occupation there were
INDIAN J TRADITIONAL KNOWLEDGE VOL 10, NO. 4, OCTOBER 2011
service holders (7), house wives (10), businessmen
(9), students (6) and unemployed (1). Seven
participants withdrew due to scheduling conflicts.
The participants were selected on the basis of
seven point scoring system of modified Hamilton’s
Brief Psychiatric Rating Scale. None of the
participants reported self-perceived adverse events,
nor were any observed by the monitoring physician.
Generalized Anxiety Disorder (GAD) is a cardinal
symptom of many psychiatric disorders and an
almost inevitable component of many medicinal
and surgical conditions. Symptoms of anxiety
commonly associated with panic disorder,
agoraphobia, obsessive-compulsive disorder,
eating disorder and many personalities disorders19.
Table 2 displays the overall effects of ACE
on subjective outcome reports results from the five
self reported questionnaires in all eight domains.
The results indicated that ACE ingestion (500 mg
capsule, twice daily for 60 days) significantly
attenuated anxiety-stress-disorders. The overall
clinical features also improved after the treatment.
For our primary outcomes, we observed a 23.3%
improvement in self-perceived stress. The state
and trait anxiety scale reported overall changes
from baseline of 95 and 18.9%. The depression
scale improved by 22.5%. Adjustment score
improved by 22.8%. Each of these results was
statistically significant with P-values all <0.0001.
Attention score demonstrated a modest improvement
of 9.2%; however, this was not statistically
The present clinical trial supports the contention
that, two-month regular administration with
Vaca or Acorus calamus reduced stress, attenuated
anxiety, negated depression and enhanced
adjustment and attention in human subject without
any side effects like vertigo, nausea, and dizziness
or mental weakness. The treatment also helped
in mental overwork in daily life. These observations
clearly indicate that ACE has potential action
in the regulation of hypothalamic–pituitary–adrenal
(HPA) axis especially, during stress related
disorders in human. The findings of this trial
should be of interest to physicians and patients
alike. It appears that Vaca or Acorus calamus may
be a safer alternative to Benzodiazepines for the
therapy of stress related clinical disorders.
Authors are grateful to Department of Science &
Technology, Government of West Bengal, India for
providing research grant.
Table 2—Effect of Vaca or Acorus calamus rhizomes extract on GAD in human Psychological Rating Scales (score)
[Values are mean ± SD of 33 participants]
Baseline (Day 0) Visit I (Day 30) % Change p-value Visit II (Day 60) % Change p-value
Anxiety 94.96±7.80 85.36±9.22 -10.1 0.001 77.0±9.05 -18.9 0.001
Stress 77.93±9.25 66.96±8.02 -14.1 0.001 59.75±7.60 -23.3 0.001
Depression 63.36±7.15 55.96±6.82 -11.6 0.001 49.06±8.34 -22.5 0.001
Adjustment 41.90±7.12 46.81±6.90 -10.4 0.02 51.51±6.17 -22.8 0.001
Attention 3.24±0.85 3.34±0.62 -3.1 NS 3.54±0.75 -9.2 NS
The dose of ACE is 500 mg capsule, twice daily , p.o. after meal
The results were statistically compared to baseline (before treatment) using Chi-Square test
Per cent change over baseline
NS = non-significant
Table 1—The distribution of subjects for trial
Total Subjects (N) 33
Average age (36.2 yrs)
<18 years 0
18-35 years 17
36-50 years 12
>50 years 4
Service holder 7
House wife 10
BHATTACHARYYA et al.: VACA ON GENERALIZED ANXIETY DISORDER
1 Chrousos GP & Gold PW, The concept of stress and stress
system disorders, JAMA, 267 (1992) 1244.
2 Murray CJL & Lopez AD, The global burden of disease: A
comprehensive assessment of mortality and disability from
diseases, injuries and risk factors in 1990 and projected to
2020. Report on Behalf of the WHO and World Bank,
Harvard University Press, Cambridge, USA, 1996.
3 Feldman RS, Meyer JS & Quenzer LF, Principles of
Neuropharmacology, (Sinauer Associates Inc., Sunderland),
4 Wagner H, Norr H & Winterhoff H, Plant adaptogens,
Phytomedicines, 1 (1994) 63.
5 Sushruta Samhita, commentary by Dalhana, edited by Jadavji
Trikamji Acarya, (Chaukhambha Orientalia, Varanasi &
6 Vaidya ADB, The status and scope of Indian medicinal
plants acting on central nervous system, Indian J Pharmacol,
26 (1997) 340.
7 Mishra LC, Scientific Basis for Ayurvedic Therapies, (CRC
Press, New York), 2004.
8 Rathee P, Chaudhary H, Rathee S & Rathee D, Natural
memory boosters, Pharmacog Rev, 4 (2008) 249.
9 Mukherjee PK, Venkatesan K, Mal M & Houton P, Acorus
calamus scientific validation of Ayurvedic tradition from
natural resources, Pharmaceutical Biol, 45 (2007) 651.
10 Sharma H, Chandola HM, Singh G & Basisht G, Utilization
of Ayurveda in health care: An approach for prevention,
health promotion, and treatment of disease, J Altern
Complement Med, 13 (2007) 1135.
11 Vohora SB, Shah SA & Dandiya PC, CNS studies on an ethanol
extract of AC rhizomes, J Ethnopharmacol, 28 (1990) 28.
12 Rammington’s The Science of Practice of Pharmacy. 20th
edn, (London: Lippincott Williams & Wilkins), 2001.
13 Hamilton M, The assessment of anxiety state by rating,
Br J Med Psychol, 32 (1959) 50.
14 Jacobson E, Modern treatment of tense patients, (Springfield,
New York), 1970.
15 Bhattacharyya D, Jana U, Debnath PK & Sur TK, Initial
exploratory observational pharmacology of Valeriana
wallichii on stress management : A clinical report, Nepal
Med Coll J, 9 (2007) 36.
16 Hicks CM, Research methods in clinical therapists,
(Churchill-Livingstone, New York), 1999.
17 Ray O, The revolutionary health science of
psychoendoneuroimmunology : A new paradigm for
understanding health and treating illness, Ann NY Acad Sci,
1032 (2004) 35.
18 Bhattacharyya D, Jana U, Debnath PK & Sur TK, Controlled
programmed trial of Ocimum sanctum leaf on generalized
anxiety disorders, Nepal Med Coll J, 10 (2008) 176.
19 Nutt DJ, Overview of diagnosis and drug treatments of
anxiety disorders, CNS Spectr, 10 (2005) 49.