Differences between pastes and ointments
(i) Pastes
generally contains a large amount (50%) of finely powdered solids. So they are
often stiffer than ointments.
(ii) When
applied to the skin pastes adhere well, forming a thick coating protects and
soothes inflamed and raw surfaces and minimizes the damage done by scratching
in itchy conditions such as chronic eczema. it is comparatively easy to confine
pastes to the diseased areas whereas
ointments, which are usually less viscous, tend to spread on to healthy skin,
and this may result in sensitivity reactions if the preparations contain a
powerful medicament such as dithranol.
(iii) Because
of the powder contents pastes are porous; hence, perspiration can escape. Since
the powders absorbs exudate, pastes with hydrocarbon base are less macerating
than ointments with a similar base.
(iv) They
are less greasy than ointments but since their efficacy depends on maintaining
a thick surface layer they are far from attractive cosmetically.
(v) Most
of the pastes are unsuitable for treating scalp conditions because they are
difficult to remove from the hair.
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