This document discusses various types of drugs that act on skin and mucous membranes. It describes emollients as bland fatty materials that soften and moisten skin, examples include oils and fats. Demulcents soothe irritated mucous membranes and form a protective layer, examples provided are glycerin and propylene glycol. Adsorbents and protectives inactivate irritants by binding to them or providing a protective layer, with examples like starch, zinc oxide and mineral oil. Other agents discussed are astringents that dry skin, counterirritants that relieve pain, keratolytics that loosen skin, and skin disinfectants that reduce bacteria.

1. Drugs acting on Skin & Mucous
membranes
Presented by:-
Dr.Archana
Assistant Professor_cum_Jr .Scientist
Deptt.Of Pharmacology & Toxicology
Bihar Veterinary College, Patna

2. Content of chapter
*Emollients
*Demulcents
*Adsorbents & Protectives
*Astringents
*Counter irritants
*Keratolytics
* Skin disinfectants

3. EMOLLIENTS
These are bland (mild, gentle) fatty
materials often used to soften or moisten
the skin. These are primarily useful for
treating the skin conditions resulting from
water soluble irritants and air borne
bacteria.
eg:-
 Vegetable Oils: Olive oil, Corn oil,
Almond oil,
 Animal fats: Lanolin, Lard, Whale oil.
 Hydrocarbons: Paraffin, Mineral oil,

4. DEMULCENTS
Demulcents are inert substances
which sooth and relieve irritation,
primarily involving the inflamed/
injured mucous membranes, these are
generally high molecular weight
compounds that are water soluble and
function by alleviating irritation. They
form a protective layer over the
irritated surfaces.
e.g. Glycerine, Propylene glycol, Gum
tragacanth.

5. ADSORBENTS & PROTECTIVES:
These are finely powdered, inert, insoluble solids
capable of inactivating the irritants by binding to
them. They exert physical protection to skin or
mucous membranes.
*Adsorbents act by binding gases, toxins and some
organisms (such as bacteria) to prevent
exposure to the damaged skin surface.
e.g. Starch, CaCO3, Talc, Titanium dioxide, ZnO &
Boric acid.
* Protectives function by providing an occlusive
layer of protection from the external environment or
by providing mechanical support to the affected
area.
e.g. Kaolin, Lanolin, Mineral oil, Olive oil,
Petroleum.

6. ASTRINGENTS
Astringents are agents that precipitate
protein, toughen the skin, promote
healing and dry the skin when applied
topically.
eg: Callamine lotion, ZnO ointment, tannic acid
etc.
Astringents have limited uses in veterinary medicine today.

7. COUNTERIRRITANTS
These are agents used to produce
hyperaemia in an attempt to relieve pain
and promote healing of tissues beneath
skin after application over the skin, the
increased blood supply results in a
greater concentration of blood-borne
anti-disease factors such as leucocytes,
increased nutrition and an improved
removal of waste products by the venous
and lymphatic systems.
Eg:- red iodide of mercury (25%),

8. Keratolytics
Keratolytics are the agents acts by
loosening keratin layer of the skin,
which facilitates the desquamation of
stratum corneum; they destroy
excessive granulation, minor tumour
and warts on skin.
 Eg:-Salicylic acid, Benzoyl peroxide
Resorcinol

9. SKIN DISINFECTANTS
Removal or reduction in bacteria on
the skin by disinfectants is a useful
part on the treatment of pyodermas.
These agents also used used for skin
disinfection prior to surgery.
e.g. :- Povidone iodine, chlorhexidine,
cetrimide & hexachlorophene, benzoyl
peroxide etc.