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Composition
Paradichlorobenzene............................................2 %
Benzocaine.......................................................2.7
%
Chlorbutol.............................................................5%
Terpentine
Oil......................................................15%
Indications
Benotol is used in
the ear to help relieve the pain, swelling, and congestion of some
ear infections. It will not cure the infection itself. An
antibiotic will be needed to treat the infection.
Description
Local
anesthetic drugs act mainly by inhibiting
sodium
influx through sodium-specific
ion channels
in the
neuronal
cell membrane,
in particular the so-called voltage-gated sodium channels. When
the influx of sodium is interrupted, an
action potential
cannot arise and signal conduction is inhibited. The receptor site
is thought to be located at the cytoplasmic (inner) portion of the
sodium channel. Local anesthetic drugs bind more readily to "open"
sodium channels, thus onset of neuronal blockade is faster in
neurons that are rapidly firing. This is referred to as state
dependent blockade.
Local
anesthetics are weak
bases
and are usually formulated as the hydrochloride salt to render
them water-soluble. At physiologic
pH
the protonated (ionised) and unprotonated (unionised) forms of the
molecule exist in an equilibrium but only the unprotonated
molecule diffuses readily across cell membranes. Once inside the
cell, the lower pH results in the molecule being protonated, thus
inhibiting its passage back out of the cell. This is referred to
as "ion-trapping". In the protonated form, the molecule binds to
the local anaesthetic binding site on the inside of the ion
channel near the cytoplasmic end.
Acidosis such as caused by wound infection partly
reduces the action of local anesthetics. This is partly because
most of the anaesthetic is ionised and therefore unable to cross
the cell membrane
CONTRAINDICATIONS
Known allergy or
hypersensitivity to benzocaine.
Dosage:
As per the physician’s advice.
Presentations
5ml/10ml Ear Drops |
Quality
