Monograph: |
Zinc Oxide
A white or faintly yellowish-white, odourless, amorphous,
soft powder, free from grittiness. It gradually absorbs carbon
dioxide from air.
Practically insoluble in water and in alcohol: it dissolves in
dilute mineral acids.
Black discoloration has been reported when zinc oxide and
glycerol are in contact in the presence of light.
Uses and Administration
Zinc oxide is mildly astringent and is used topically as a
soothing and protective application in eczema and slight ex-
coriations. in wounds, and for haemorrhoids. It is also used
with coal tar or ichthammol in the treat-
ment of eczema. Zinc oxide reflects ultraviolet radiation and
is used in sunscreens.
In the USA the name calamine is used for zinc oxide with a
small proportion of ferric oxide.
Zinc oxide is used as the basis for the production of a number
of dental cements. Mixed with phosphoric acid it forms a hard
material composed largely of zinc phosphate; mixed with
clove oil or eugenol. it is used as temporary dental tilling.
Complications of dental use. Solitary aspergillosis of the
maxillary sinus in 29 of 30 patients was associated with zinc
oxide from overfilled teeth. Treatment consisted of removal
of the fungal ball containing the zinc oxide; no antifungal
treatment was necessary. Zinc oxide has been shown to accel-
erate the growth of Aspergulus fumigatus.
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