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2447| International Journal of Pharmaceutical Research | Apr - Jun 2021 | Vol 13 | Issue 2
Revi ew Article
Steam inhalation in treatment of the COVID-19
patients: A Review
DR. SANTOSH KUMAR SWAIN1*, SMARITA LENKA,MSC1, SOMADATTA DAS,MA2
1Department of Otorhinolaryngology, IMS and SUM hospital, Siksha “O” Anusandhan University, K8,
Kalinganagar, Bhubaneswar-751003, Odisha, India.
2Central Research Laboratory, IMS and SUM hospital, Siksha “O” Anusandhan University, K8,
Kalinganagar, Bhubaneswar-751003, Odisha, India.
*Corresponding Author
Email ID: santoshswain@soa.ac.in,
Received: 11.01.21, Revised: 10.02.21, Accepted: 09.03.21
ABSTRACT
Steam inhalation is widely practiced home remedies in upper respiratory tract infections or upper airway
allergy for soothing the airway and opening of the nasal passages. Clinical presentations of the upper airway
such as nasal block and nasal discharge are often relieved which improve the quality of life. Mild to moderate
symptoms of the corona virus disease 2019 (COVID-19) infections are usually benefited from the steam
inhalation. Severe symptomatic patients are often associated with dyspnea and need ventilator or oxygen, so
unable to do steam inhalation. The COVID-19 infection is highly contagious disease caused by the novel
coronavirus called Severe Acute Respiratory Syndrome Coronavirus-2(SARS-CoV-2).This virus is enveloped
virus which is sensitive to the heat and destroyed by the temperature tolerable to the human being. The
viability of the virus is usually lost at higher temperature like in steam inhalation and so useful for treatment of
the COVID-19 infections. Steam inhalation is a cheap and easily available therapeutic modality for COVID-19
infection. Steam inhalation can be used as adjuvant treatment by COVID-19 patients along with use of the face
mask, social distancing and hand wash. There is little work on the steam inhalation for treatment of the
COVID-19 infections. This review article discusses on the benefit of the steam inhalation and used as an
adjuvant treatment during COVID-19 pandemic.
Keywords: Steam inhalation, COVID-19, SARS-Co-V-2, home remedy.
INTRODUCTION
COVID-19 infection is a contagious disease of
respiratory tract caused by the novel virus, called
severe acute respiratory syndrome coronavirus 2
(SARS-CoV-2) [1]. It is highly infectious disease
which spreads all over the world in short span of
the time. On March 11th, 2020, the World Health
Organization (WHO) declared COVID-19 as a
global pandemic [2]. The common symptoms of
the COVID-19 infections are cough, fever, nasal
congestions, rhinorrhea, sneezing, headache,
sore throat, altered taste and smell sensations [3].
In severe cases, patients may land in acute
respiratory distress syndrome (ARDS) and
respiratory failure [4]. The knowledge of the
medical community regarding clinical
manifestations and treatment of the COVID-19
infection is extremely dynamic as the behavior of
this virus is still not established. During this
current pandemic, it is usually challenging to find
out the possible treatment of COVID-19 infection
and break the chain of transmission. The
effective treatment for the COVID-19 infections is
currently under the urgent investigation. Presently
there is no evidence of the randomized clinical
trials regarding the specific treatment which
improves the patient outcome in COVID-19
infection [5]. Steam inhalation is a traditionally
used as home remedy in patients suffering from
upper respiratory tract infections and common
colds. The steam inhalation loosens the mucus
and cleans the nasal passages and reduces the
inflammation of the mucosal lining of the upper
airway or inhibits the replication of the viruses
because of the heat of the steam [6]. In COVID-
19 infections, currently emphasis on the
preventive strategies on social distancing, use of
the face mask and hand washes [7]. The use of
the steam inhalation has been suggested to be
useful for reducing the upper airway symptoms,
transmission and viral shedding. There are limited
medical literatures for steam inhalation and
treatment modality of the COVID-19 infection.
This review article is aimed to discuss details of
the epidemiology, effect of the steam on the
SARS-Co-V-2 virus, technique of the steam
inhalations, complications and clinical benefits in
COVID-19 infections. This article surely helps to
provide more awareness among the primary care
physicians or clinicians about the potential
effectiveness of the steam inhalation for treating
the COVID-19 infections.
ISSN 0975-2366
DOI: https://doi.org/10.31838/ijpr/2021.13.02.321
Dr. Santosh Kumar Swain et al / Steam inhalation in treatment of the COVID-19 patients: A Review
2448| International Journal of Pharmaceutical Research | Apr - Jun 2021 | Vol 13 | Issue 2
METHODS OF LITERATURE SEARCH
Research articles regarding steam inhalation in
COVID-19 patients were searched through a
multiple approach. First we conducted an online
search of the PubMed, Scopus, Google Scholar
and Medline database with the word steam
inhalation, COVID-19 pandemic, SARS-CoV-2
infections and treatment with steam inhalation. A
search strategy using PRISMA (Preferred Reporting
Items for Systematic Reviews and Meta-Analysis)
guidelines was developed (Fig. 1).Randomized
controlled studies, observational studies,
comparative studies, case series and case reports
were evaluated for the eligibility. This paper
focuses only on the steam inhalations and its
benefits in COVID-19 patients. The search articles
related with COVID-19 infections and its
treatment with other than steam inhalations are
excluded. Review articles with no primary research
data were also excluded. The abstracts of the
published article were identified by this search
method and other articles were identified
manually from the citations. This review article
reviews the steam inhalations in treatment of the
COVID-19 infections including its epidemiology,
history, techniques, clinical benefits and its
complications. This review article presents a
baseline from where further prospective trials can
be designed and help as a spur for further
research in this clinical entity where not many
studies are done.
Epidemiology
Currently the global attention is mainly on the
COVID-19 infections.COVID-19 is a highly
contagious and dreaded infection of the
respiratory system due to novel virus SARS-CoV-2
[8]. The first case of COVID-19 was reported in
Wuhan, China in late December 2019 where the
outbreak of this novel corona virus happened and
now called as SARS-CoV-2(severe acute
respiratory syndrome corona virus 2) which
spreaded worldwide in short span of time [9].
COVID-19 spread to around 199 countries by
March 26, 2020 with more than 462680 positive
cases and approximately 20834 deaths [10]. The
pandemic of the COVID-19 is showing a grim
and tragic situation worldwide in current days. It
is affecting on the global economy along with
clinical practice for routine patient care. The
association between the COVID-19 infections and
acute respiratory distress syndrome (ARDS) pose a
challenge to the clinicians [11]. The whole World
is presently under the big threat for COVID-19
infections. It affected more than 6.5 million
people globally by May 2020 and death toll has
more than 380,000 [12]. The widespread
transmission and infectivity of the COVID-19 lead
to an unrestricted health threat to the planet [13].
COVID-19 has spread almost all countries of the
world. School and colleges are closed with people
locked in their homes, no buses, no trains, no
flights and also no economic activity. It almost
paralyses the human activity in current situation.
Heat is one of the ancient forms of the microbial
control and considered as a common technique
for eradicating the pathogens. Steam inhalation is
popular home remedy for upper respiratory tract
infections. The general practitioners often
recommend it for patients with sinonasal or upper
airway infections. This technique is recommended
by clinicians or General practitioners (GPs) for
treatment of the patients with common colds or
croups in Netherlands, USA and UK [14]. The
steam inhalation has been practiced since
centuries as a mean of the treatment for influenza
virus or common flu and along with. Steam
inhalation was practiced by ancient Egyptians
where peoples were benefited and even today this
therapy is helpful to treat several health ailments
especially infections of the respiratory systems.
Heat based treatment for upper respiratory viral
infections are standard offerings in different
wellness establishments. These heat based
treatment include steam inhalation, hot springs,
saunas, hammams, steam rooms, steam baths
and hot mud. These are usually used as both
therapy and recreation [9].
COVID-19 Virus
COVID-19 infection is caused by the SARS-CoV-
2.This virus is an encapsulated or enveloped
positive strand RNA virus (Fig.2) which can be
classified into four genera such as alpha, beta,
delta and gamma. Out of these 4 types, alpha
and beta are known to infect human beings [15].
The size of corona virus ranges from 60 nm to
140 nm with spike like projection from the surface
as a crown like appearance under electron
microscope, so the name corona virus [16]. The
spikes over surface of the SARS-CoV-2 are made
up of glycoprotein which act as critical for binding
to the host cell receptors and play an important
role in severity of the infections of the host [15].
The incubation period of SARS-CoV-2 virus
ranges from 1 to 14 days with a median of 5-6
days. Although recent study document that the
incubation period may extend to 24 days [17]. A
longer incubation has implication in quarantine
policies and prevention of the spread of the
disease. Coronavirus is similar to the influenza
virus and SARS-Co-V2 .The influenza virus and
coronavirus show a strong heat correlation. The
stability of the virus varies at different
temperatures and relative humidity on smooth
surfaces. The dried SARS-Co-V-2 virus on smooth
Dr. Santosh Kumar Swain et al / Steam inhalation in treatment of the COVID-19 patients: A Review
2449| International Journal of Pharmaceutical Research | Apr - Jun 2021 | Vol 13 | Issue 2
surfaces retain its viability for over five days at
temperatures of 22 to 25 0C and relative humidity
of 40 to 50% which is a typical air-conditioned
environment [18]. However, the viability of the
virus is usually lost at higher temperatures and
higher humidity e.g. 38 0C and relative humidity
of > 95%.Steam has a temperature of about to 7
0C to 80 0C which is well above the instability
temperature of the SARS-CoV-2 virus. In humans
and Guinea pigs, the Influenza virus also shows a
similar pattern. Majority of the influenza virus is
also inactivated above the 30 0C [19]. The
enveloped viruses like rhinoviruses and
coronaviruses are usually active in cool dry
environments, which are often associated with
increased chance of the respiratory tract
infections, including the SARS-CoV-2 [20].
History of steam inhalation
The practice of the steam inhalation came to
clinical practice in Europe at the time of Victoria
and has been used for clearance of the
respiratory secretions in the upper airway in
common cold and croup [21, 22]. It was
originally practiced by inhaling the steam directly
over the bowel with boiling water. Then modern
vaporizes came to the market where water is
heated with help of the electrodes immersed in
the water and may involve addition of the scented
oils [23]. The National Institute for Clinical
Excellence (NICE) is presently recommends that
the steam inhalation can be used for symptomatic
relief of the upper airway congestions and the
virus destroy the common cold virus [6].
Steam inhalation in covid-19 patients
The enveloped viruses like SARS-CoV-2 are
usually sensitive to the heat and often destroyed
by the temperatures tolerable to the human
beings. Inhalation of the humid and hot air
increases the temperature of the nasal mucosal
membrane in rhinosinusitis and leading to
decrease the chemical secretion from the mast
cells [24]. One study demonstrated that the level
of the histamine in nasal mucus in case of allergic
rhinitis or common cold reduced significantly
after inhalation of the steam, causing decreased
nasal block and vascular leakage [25]. Steam
inhalation relieves the cold symptoms by reducing
the Rhinovirus and coronavirus. It also lowers
different inflammatory process and
immunological responses as in viral infections of
the upper airways. Steam inhalation helps to
increase moisture in the nasal mucosa and
reduce the release of histamine and tryptase as
heat could lowers the reaction between the
allergens and mast cells or basophils. In addition
to this, steam also stabilizes the nasal mucosa
and so decreases the mucus production and
vascular permeability [26]. Moreover, steam
inhalation prevents nasal itching, sneezing and
nasal block because of allergen challenge [27]. In
one study on Thai population, the effect of the
steam inhalation (420C to 440C) on nasal block
and other nasal symptoms such as nasal itching,
running nose, sneezing, eye symptoms,
headache, facial pain and postnasal drip showed
significant improvement after steam inhalation
[28]. The inhaled steam condenses over the nasal
mucosa and leads to increased moisture level
over the nasal mucosa [29]. In addition to this,
steam inhalation also decreases the osmolality of
the mucus, so that the phlegm and thick nasal
mucus secretions from the nasal glands are
reduced [30].
Techniques of steam inhalation
The COVID-19 patients are advised to take steam
inhalation twice to thrice daily by ordinary
steamers available in market or can be simple
boiling of water and inhalation of the resulting
steam [30]. Other than steamer, a bowel or a
pan may be used for steam inhalation. The water
inside the steamer is usually boiled with help of
electricity. Once the water is boiled, it produces
steam and can be used for inhalation. If it will be
used for children, the boiling water should be
cooled before used as steam inhalation. At the
time of steam inhalation, the head and neck
should be covered with a towel or thick cloth, so
that steam will directly enter into the nostrils.
Steam should not escape the cloth or towel. The
patient should also breaths the steam but not to
stress enough if uncomfortable. The steam
inhalation should continue for few minutes and
repeat it 2 to 3 times a day. Steam inhalation is a
time tested remedies for upper airway
congestions. So after this inhalation, patients will
be relieved from nasal congestions and clearance
of the secretions from the sinonasal cavities.
There is loosening of the mucous after steam
inhalation and it coughed out. It helps in
reduction of the hypoxia and make patients
symptom free. Steam inhalation is an easily
available technique and affordable addition to
the treatment for COVID-19 infections which curb
the severity of the infections and transmission of
the SARS-CoV-2.
Clinical benefits of steam inhalation in covid-19
pandemic
The symptoms of the COVID-19 infections are
usually drastically reduced after administration of
the steam. The steam inhalation is postulated to
give relief of the respiratory congestion through
loosening the respiratory secretions [31]. Steam
inhalation is helpful to release the pressure which
build in the paranasal sinuses and facilitates the
secretions or mucous from the sinuses. It also
makes smoothening of the mucus membrane of
Dr. Santosh Kumar Swain et al / Steam inhalation in treatment of the COVID-19 patients: A Review
2450| International Journal of Pharmaceutical Research | Apr - Jun 2021 | Vol 13 | Issue 2
the sinonasal area and clears the congestions in
the nasal cavity. It also helps to decrease the
chance of the headache. The steam inhalation is
also helpful to stop further transmission of the
infection. The reversal of the symptomatology in
COVID-19 patients are considered as an
effectiveness of the steam inhalation and thought
as a welcome sign after steam inhalation. Steam
inhalation helps to release of the endorphins in
the body which helps the person stress free and
feeling good in the COVID-19 pandemic. The
release of the endorphins also facilitates the good
sleep in the night. The steam helps to open the
airways, which try to improve the breathing. An
appropriate respirator causes relaxation of the
mind and body. Heat of the steam inhalation
increases the blood circulations in the body which
helps to relaxation of the muscles. Steam
inhalation helps to reduce the cortisol level in the
circulation. Cortisol is a hormone which responds
to the mental or physical stress of the body. If the
cortisol level is deceased in the body, a person
feels more relaxed and happier. It also lowers the
inflammatory process and immunological
responses by viral infections of the respiratory
tract specifically upper airway. Steam inhalation
surely relieves nasal symptoms such as nasal
block, itching, sneezing, running nose, postnasal
drip, facial pain and headache in COVID-19
patients. The steam inhalation improves the ciliary
function, so helps in mucociliary clearance,
decongestion, enhances the breathing and reduce
the cough[32]. Steam inhalation is one of the
effective adjuvant treatments in asymptomatic and
symptomatic COVID-19 patients. It usually
relieves the respiratory symptoms and helps to
speedy recovery of the COVID-19 patients. The
steam inhalation is one of the effective adjuvant
treatments for COVID-19 infections.
Complications of steam inhalation
Steam inhalation is a common home practice for
upper airway infections like common cold. It has
the potential to cause scald injuries because of
unintentional contact with hot water steam [33].
Steam inhalation may be hazardous to the
pediatric age patients and should be done
carefully. Steam inhalation may result in scalds
and even require hospitalization for this
complications and disfigurement. Initially
practiced by inhaling the steam over the boiling
water in a bowel has high chance of
complications like scald injury but as the methods
of steam inhalation is evolving to modern steamer
or vaporizers where boiling water will not come in
direct contact with skin. Scald injuries due to
steam inhalation cause a significant impact in
terms of the cost and hospital stay. Public
awareness regarding the complication of steam
inhalation and primary preventive measures can
minimize the frequencies of such injuries. ‘First do
no harm’ is a basic principle of any medication
practiced on the human being. So, people should
be careful and aware about this complication
before using the steam inhalation.
CONCLUSION
Steam inhalation is a cheap, convenient and
widely available therapeutic option for prevention
of the COVID-19 infection. Easily availability and
relatively low cost of the steam inhalation make
an attractive option for treatment of the viral
infections of the upper airway. Steam inhalation
should be permitted as an adjunct to the hand
wash, social distancing and face mask for
effective controlling the COVID-19 infections in
this current pandemic. Further studies are needed
in a larger scale among Asian and Western
countries for strong establishment the
effectiveness of the steam inhalation in COVID-19
patients.
Conflict of interest: Nil
Source of Funding: Nil
Ethical clearance: NA
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Dr. Santosh Kumar Swain et al / Steam inhalation in treatment of the COVID-19 patients: A Review
2452| International Journal of Pharmaceutical Research | Apr - Jun 2021 | Vol 13 | Issue 2
FIGURE LEGENDS
Fig.1: Methodology for literature search.
Fig.2: Structure of the COVID-19 virus (Black arrow is spike protein over lipid membrane, red
arrow indicates RNA).
