MILIARIA- AN UPDATE

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July – August 2017 RJPBCS 8(4) Page No. 1161
Research Journal of Pharmaceutical, Biological and Chemical
Sciences
Miliaria: An Update.
Manju Nagpal1, Gursharn Singh1, Paramjot1, and Geeta Aggarwal2*.
1College of Pharmacy, Chitkara University, Chandigarh- Patiala Road, Rajpura- 140401, Punjab, India
2Delhi Pharmaceutical Sciences and Research University, Sector 3, Pushpvihar, New Delhi-110017
ABSTRACT
Miliaria is an inflammatory disorder of skin particularly in humans, which is characterized by multiple
small lesions at the site of sweat pores, brought about by the blockage of sweat ducts and the resulting escape
of sweat into various levels of the skin. Thus it arises from obstruction of the sweat ducts. Miliaria is most
common in hot, humid conditions but may occur in desert regions. There are different types of miliaria
possible which are mainly based on the level of obstruction of sweat glands. The disease is mainly treated with
antimicrobial, steroids, antibiotics in case of allopathic treatment. The herbal and Ayurvedic treatment options
are also available in the market. This review discusses the types of miliaria, its pathophysiology, epidemiology
and treatment options available.
Keywords: Miliaria, Heat rash, Dermatitis, Papules
*Corresponding author

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INTRODUCTION
Miliaria is a common disorder of the eccrine sweat glands. These glands are present all over the body and
form a water based secretion that primarily helps to cool the body. Miliaria occurs in conditions of increased
heat and humidity and is caused by blockage of the sweat ducts, which results in the leakage of sweat into the
epidermis or dermis [1]. The 4 types of miliaria are classified according based on the level at which
obstruction of the sweat duct occurs:
Miliaria Crystallina
It is the mildest form, usually the blisters aren't itchy or painful and the spots tend to disappear within a
few hours or days. This is the least itchy form of the condition and there may not be any itch at all. The rash
may simply be a curious event that you notice on your skin. The superficial vesicles are not associated with an
inflammatory reaction [2].
Miliaria Rubra
In this type of miliaria, obstruction occurs deeper within the epidermis and results in extremely pruritic
erythematous papules (i.e itchy skin with redness and imflamation forming papules which don’t contain puss).
The spots are just a few millimetres in size and may look like tiny blisters. Several crops of spots usually appear
in different parts of the body. They occur mostly where there is friction with clothes. They can be very itchy -
although it may be more of an intense prickling sensation. Some areas of skin become red. The rash may occur
within days of coming into a hot climate. However, often the rash does not appear until weeks or months have
passed in the hot climate. The rash tends to go within a few days if you get out of the hot environment and
stop sweating [3,4].
On the affected areas of skin there is a reduced amount of sweat, or no sweat at all. You may feel tired
and become intolerant of heat. If you continue to sweat and the rash covers a large part of your body then you
have a small risk of developing a high temperature (fever) and/or heat exhaustion. This is because you are not
able to sweat properly to get rid of body heat.
Miliaria Profunda
Ductal obstruction occurs at the dermal-epidermal junction in this. Sweat leaks into the papillary dermis
and produces subtle asymptomatic flesh-colored papules. It is the least common form, usually in adults after
repeated events of miliaria rubra. It is caused when the blockage of the sweat ducts occurs at the level of the
middle layer of the skin (the dermis). Bigger lumps develop on the skin when you sweat. These tend to be flesh
colored as they are deeper than the miliaria rubra form. There is little itch with this type of miliaria but there is
a greater risk of developing a fever and heat exhaustion if much of the skin surface is affected.
Miliaria Pustulosa
When pustules develop in lesions of miliaria rubra, the term miliaria pustulosa is used. Also called as
white/yellow heat rash (miliaria pustulosa). Pustules form due to inflammation and bacterial infection. The
fluid inside the pustules contain puss. Miliaria pustulosa is preceded by another dermatitis that has produced
injury, destruction, or blocking of the sweat duct. These pustules may be the first signs of a skin infection [5].
PATHOPHYSIOLOGY
Basically Prickly heat (miliaria) is due to blockage of sweat ducts. You have thousands of sweat glands that
lie just under the skin surface. These secrete sweat on the surface of the skin . If the sweat duct of these glands
get blocked, the sweat seeps into the skin rather then being secreted on the skin. This causes tiny pockets of
swelling (papules) which cause miliaria (Figure 1).

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Figure1: Types of miliaria
The various events involved are as follows [6,7]
 Blockage of sweat gland ducts
 Retention of the sweat into skin
 Disruption of duct cell
Blockage of sweat gland ducts:
Basically Miliaria occurs when the sweat gland ducts get plugged due to dead skin cells or bacteria such
as Staphylococcus epidermidis. (a common bacterium that occurs on the skin which is also associated
with acne). Acute inflammation of sweat ducts is caused by blockage of pores by macerated skin. In
susceptible persons, including infants, who have relatively immature eccrine glands, over-hydration of the
stratum corneum is thought to be sufficient to cause transient blockage of the acrosyringium (most superficial
region of sweat gland duct). There is also evidence that Staphylococcus epidermidis, which may be present in
higher numbers on macerated, occluded skin, produces a polysaccharide substance that may obstruct the
delivery of sweat to the skin.
Histological examination of blockage of duct-
Histological study showed a PAS-positive diastase resistant amorphous mass deep within the
acrosyringium after 2 days of occlusion, accompanied by a periductal dermal infiltration of leukocytes. After
another 2 days the duct became clogged by an amalgam of degenerating leukocytes.This impaction sloughed
after about 3 weeks as a result of epidermal renewal. Colonies of bacteria were never found within the ducts.
It is postulated that cocci secrete a toxin which injures luminal cells and precipitates a cast within the lumen.
Infiltration by leukocytes creates an impaction which completely obstructs the passage of sweat for several
weeks.
Retention of sweat into the skin:
If hot humid conditions persist, the individual continues to produce excessive sweat, but he or she is
unable to secrete the sweat onto the skin surface because of ductal blockage. This blockage results in the
leakage of sweat en route to the skin surface, either in the dermis or epidermis, with relative anhidrosis.When
the point of leakage is in the stratum corneum or just below it, as In miliaria crystallina, little accompanying
inflammation is present, and the lesions are asymptomatic.In miliaria rubra, the leakage of sweat into the
subcorneal layers produces spongiotic vesicles and a chronic periductal inflammatory cell infiltrate in the

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papillary dermis and lower epidermis. In miliaria profunda, the escape of sweat into the papillary dermis
generates a substantial, periductal lymphocytic infiltrate and spongiosis of the intra-epidermal duct.
Eccrine duct disruption:
The primary pathogenic process in miliaria is eccrine duct disruption.
Excessive sweating leads to overhydration of the stratum corneum, which in turn leads to acrosyringeal
occlusion.
 Ducts become dilated under pressure and ultimately rupture
 Often seen in areas of friction
 This produces superficial vesicles in malpighian layer of skin on a red base
 May progress to miliaria profunda (white papules) if duct ruptures a second time
However, sweating alone is not enough to produce duct disruption and miliaria. Elevated concentrations
of sodium chloride on the skin, high humidity, occlusive clothing may lead to eccrine duct disruption from
maceration of the stratum corneum and ultraviolet radiation induced damage to epidermal cells may also
cause ductal disruption. Eccrine duct damage caused by high sodium content may lead to miliaria crystallina in
the setting of hypernatremia. In late-stage miliaria, hyperkeratosis and parakeratosis of the acrosyringium are
observed. A hyperkeratotic plug may appear to obstruct the eccrine duct, but this is now believed to be a late
change and not the precipitating cause of the sweat duct blockage [8].
Role of bacteria:-
Some people are more prone to miliaria than others. It seems that a germ (bacterium)
called Staphylococcus epidermidis may play a role. This bacterium lives harmlessly on the skin and miliaria
is not an infection. However, this bacterium makes a sticky substance. This substance combined with excess
sweat and dead skin cells may cause the blockage.Resident skin bacteria, such as Staphylococcus
epidermidis and Staphylococcus aureus, are thought to play a role in the pathogenesis of miliaria. Patients
with miliaria have 3 times as many bacteria per unit area of skin as healthy control subjects. Periodic
acid-Schiff-positive diastase-resistant material has been found in the intraductal plug that is consistent with
staphylococcal extracellular polysaccharide substance (EPS). In an experimental setting, only the strains
of S.epidermidis that produce EPS can induce miliaria [6]. Condita albicans was also found presnt sometimes at
the site of miliaria
EPIDEMIOLOGY
Prickly heat (miliaria) can develop in anyone at any age. However, it is most common in children and
babies, as their immature sweat glands are more prone to becoming blocked. It is particularly common in
newborn babies but soon clears. Another common time for the rash to occur is when people travel to a
warmer climate and sweat more than usual. Miliaria can also occur in cooler climates when sweating is a
problem. For example, people who lie on their back for long periods due to illness may get miliaria on their
back. This can occur after having a stroke or a major operation. It can also occur if you are wearing too many
clothes or the bedding is too warm. Miliaria is seen in all age groups and sexes worldwide. Miliaria profunda is
seen mostly in adults while miliaria crystallina and miliaria rubra occur in both children and adults.
Miliaria crystallina occurs in 1.3% to 4.5% of infants and congenital cases have been described. Miliaria
rubra affects 4% of neonates [9]. A survey showed that pediatric patients in north eastern India showed an
incidence of miliaria up to 1.6% [10]. Miliaria crystallina and rubra occur globally while miliaria profunda is
usually only seen in tropical environments. Miliaria crystallina is most commonly seen in febrile diseases,
situations in which occlusive clothing prevents dissipation of heat and moisture such as in bundled infants,
after sunburn under hot and humid climatic conditions, and in newborns immediately after delivery in the
setting of maternal fever. In addition, miliaria crystallina has been associated with underlying hypernatremia
both in adults and children. Miliaria rubra occurs most commonly in hot and humid environments with use of
occlusive clothing, affecting up to 30% of individuals with a maximal incidence after 2 to 5 months of exposure
to a tropical environment.

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In miliaria profunda occurs due to following multiple episodes of miliaria rubra. Miliaria profunda is usually
only seen in tropical environments. Miliaria occurs in individuals of all races, although some studies show that
Asians, who produce less sweat than whites, are less likely to have miliaria rubra.
TREATMENT OF MILIARIA
Allopathic Treatment
In general the rash of miliaria will resolve without intervention if it is in mild form. As miliaria is caused in
hot and humid conditions thus the primary treatment and prevention for miliaria is to control heat and
humidity so that excessive sweating doesn't occurs. This can be done by removing occlusive clothing, moving
to a cooler climate, limiting activity, frequent cool showers or baths with mild soaps and providing air
conditioning.
In most of the cases the pimple like blisters are formed containing fluid inside of them, it is recommended
to drain that fluid out of them either at home in a sterile environment or by means of a medical procedure. If
the fluid is not drained then the fluid increases in viscosity and the blisters may become red and spread
underneath the skin, making the conditions more adverse. When proceeding to drain the fluid at home then
firstly the area affected should be sanitized and then followed by draining the blister by a sterilized needle or
lancet [11].
Various topical formulations are available in the market to treat heat rash, in the form of lotions,
ointments, powders, gels. These all generally include a cleansing agent, an antiseptic or antimicrobial, a cooling
agent, anti inflammatory agent and an anti-pruritic agent with some additives for fragrance or color.
Cleansing agents are used in various dermatological disorders to remove dead skin, sebum, dirt and even
moisturize the skin. The cleansing of the skin helps to clear the obstruction of the sweat gland’s ducts and thus
treating miliaria. Soothing agents nourishes and soothes the skin and anti microbial agents are used to
eliminate and stop the growth of micro organisms such as S.epidermis and S.aureus which play a major role in
causing miliaria by blocking the sweat gland duct. The anti-pruritic, anti inflammatory and cooling agents are
used to get relieved from symptoms of miliaria like itch, redness and inflammation of the skin [11,12].
In addition to these agents, mild topical steroids like corticosteroids and hydrocostisone are also used to
relieve the symptoms. Generally steroids work by reducing inflammation and and soothing the irritation.
Some of the widely used components include calamine (for soothing the skin), menthol as an anti-pruritic
and cooling agent, boric acid and neem are used as an antimicrobial and zinc oxide as antiseptic and for its
wound healing properties. Ingredient like turmeric provide various benefits as they act as cleansers ,speed up
wound healing, natural antiseptic, anti-pruritic, and also provides anti inflammatory action.
The application of lanolin topically, shows great improvements in patients with miliaria profunda [13].
Except of topical applications, miliaria can also be treated by help of oral medication. Retinoids ,vitamin C
and vitamin A have shown variable rate of success in treatment , but no controlled trials have been done to
show the magnitude of effectiveness of these systemic therapies.
Herbal Treatment
The most common remedies for prickly heat rash include oatmeal bath, gentle massage with aloe vera gel,
and application of paste of baking soda, sandalwood powder, fuller’s earth, margosa leaves, neem leaves and
basin. The pastes are made either by mixing the fine powder of the ingredient with water or rose water. A
mixture of chamomile and powdered calendula mixed with cornstarch is also very effective and soothes the
skin. These remedies mostly work by moisturizing and soothing the skin along with providing a mild
antimicrobial and anti-pruritic action. In case of miliaria profunda and miliaria pustulosa it is recommended to
seek a medical professional [14, 15, 16].

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Formulations
Various formulations are available in the market to treat miliaria, like ointments, gels, lotions, creams,
powders etc (Table 1). Out of all these the powder preparations are widely used as powders remain for a
longer time over the skin and kill bacteria dispersed into the bed of the powder applied, also it provides a dry
surface which is a major aspect as dry surface leads to better healing of miliaria [10].
Preparations like ointments and creams are preferably made with aqueous base rather then an oily base
because aqueous base provides many advantages as it provides faster absorption, easy spreading over skin
and thus easy applications , they don’t breakout unlike oil based formulations, they don’t leave any marks and
doesn’t clog the skin pores. Whereas the oil based creams or ointments can clog the skin pores or form a layer
over a skin which is unwanted in treatment of miliaria.
Table1: Herbal treatment available in market
Name
Company
Ingredient
Application
Reference
Prickly heat baby
powder
Himalaya
Khus-khus,
yashada bhasma,
jaitun oil,
vatada, ushira
Powder is gently
applied
on the skin surface
17
Magicool plus
Prickly heat spray
France Med.
pharma
Aqua,
Allantoin,
Me0thoxymethane,
Betain,
hesperidin,
Menthyl lactate,
Oryzanol
Aerosol is sprayed on
the affected area
18
Prickly heat spray
Naissance
Aqua,
Hamamelis viginia,
Alcohol,
Anthemis nobilis oil,
Eucalyptus oil,
Lavandula angustifolia
oil
Aerosol is sprayed on
the affected area
19
Dermacool plus
cream
Dermacool
Aqua,
White soft Paraffin,
Emulsifying Wax,
Paraffinum Liquidum,
Menthol,
Phenoxyethanol
Apply on low quantity
and gently massage on
the skin
20
Snake brand Prickly
heat powder
The British
dispensary.co
Talc,
Kaolin,
Camphor,
Menthol,
Triclocarban,
C177491,
C177492
Apply gently on the
skin
21
Resinol medicated
ointment
Resical.inc
Petrolatum,
Resorcinol,
Calamine,
Cornstarch,
Lanolin,
Zinc oxide
Gently massaged over
the effected area
22
Praval pishti
Patanjali
Coral calcium,
Rose water
Taken orally twice a
day with dose not
exceeding 2500 mg
23

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AYURVEDIC TREATMENT
It is considered as an holistic concept and a natural system of health management which has been
originated 5000 years ago. Ayurveda creates an overall health and takes into consideration that body, mind
and soul is interconnected. The state of being is based on the principle of doshas in Ayurveda. The three
doshas are- Vatta, Pitta and Kapha. Any imbalance in any of these doshas will lead to a diseased state. These
doshas are further comprised of different elements (Table 2). According to ayurveda the world is made of 5
fundamental elements, these are aakash (ether),vaayu (wind), agni (fire), jal (water),and prithvi (earth) [24,
25] .
Table 2: Different elements in doshas in Ayurveda
Name of dosha
Element 1
Element 2
Vata
Earth
Air
Pitta
Fire
Water
Kapha
Water
Earth
Vata dosha is concerned with the body’s motion, the pitta dosha is concerned with body’s metabolism
and kapha dosha is concerned with body’s structure.
The Pitta dosha is further of 5 types - these are pachaka, ranjaka, sadhaka, alochaka , bhrajaka. The
bhrajaka type is responsible for them maintaining skin color, texture, and temperature and hence the miliaria
or heat rash occurs due to the imbalance in bhrajaka-pitta dosha. Various other symptoms of pitta dosh
imbalance include visual problems, peptic ulcer, skin diseases, premature baldness, excessive body heat, acne,
boils, and inflammatory bowel disease. Therefore all the remedies which are used to balance pitta dosha can
be used to treat miliaria.
The treatment can be done both externally by application of various oils, pastes and other remedies or by
internal intake of various Bhasma, Rasa etc [26, 27].
External remedies include application of various oils, powders, emulsions and pastes over the effected
area. these oils include Chandanadi taila, Durvadi taila and Himasagara tailam. Paste of Durva, chandana, and
ushira is made using rose water and applied over the area where the prickly heat has affected the skin. The
emulsion of onion juice and ghee are also effective and used by application over the affected area. Other
ingredients used in making these remedies include coconut oil, turmeric powder, lemon juice, red sandalwood
powder, coccum juice etc.
Internal remedies include: Kamadugdha with mouktika (contains coral and pearls), Chandrakala
rasa (possess usheera and ketaki) , Godanti bhasma (medicated ash of gypsum), Gulkhand (rose and sugar),
Sarivadyasava (contains Indian sarsaparilla), Chandanasava (acts as a coolant ), Usheerasava (has potent
diuretic properties), Pravala bhasma (formulation of coral) [28]. These all internal remedies generally reduce
sweating and act as a coolant to reduce the symptoms and treat miliaria.
UPDATES IN TREATMENT OF MILIARIA
Bansod et al., 2010 investigated that anti-microbial compounds in human sweat are an important
diagnostic and therapeutics for the treatment of skin diseases like miliaria (29). Use of topical steroids for
treatment of miliaria is most recommended because of their anti-inflammatory properties. The physicians
move top antibiotics and antifungals for prevention of secondary infection. The physicians may prescribe oral
antibiotics and antihistaminics if required.
CONCLUSION
For the prevention of miliaria, clothing must be properly laundered to adequately remove detergent
residue. While in hot environments, individuals with sensitive skin should take the necessary precautions such
as regular changing of uniforms and good personal hygiene to ensure that their skin remains as dry and clean

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as possible and drinking lots of fluids. It is also important that they seek medical advice as soon as skin
irritation or rash appears to initiate the necessary medical procedures.
ACKNOWLEDGEMENTS
The authors are thankful to Dr. Madhu Chitkara, Vice Chancellor, Chitkara University; Dr. Ashok Chitkara,
Chancellor, Chitkara University; Dr. Sandeep Arora, Director, Chitkara College of Pharmacy for providing
necessary facilities and support.
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