Nail patches have a
potential
role as drug carriers for
the topical treatment of nail diseases
such as onychomycosis, a common condition. O
ur aim
was
therefore
to develop a
systematic
and novel appr
oach to the
formulat
ion of a simple drug
-in-adhesive ungual
patch.
Twelve
pressure
-sensitive adhesives (PSAs), four backing membranes, two release
liners and three drugs
were screened
for pharmaceutical and mechanical properties
. From
this
initial
screeni
ng,
two PSAs, two drugs, one backing membrane and one release liner
were selected
for further investigation.
Patches
were prepared by
solvent
-casting and
characterised.
The patches had good uniformity of thickness and of drug content, and
showed minimal drug crystallisation during six
month
s of
storage.
Meanwhile, the d
rug
stability in the patch upon storage and patch adhesion
to the nail
was influenced by
the
nature of the drug, the
PSA
and the backing membrane
. The
reported
methodology paves
the way for a systematic
formulation
of
ungual
nail patches to add to the armamentarium of
nail medicines
. Further
, from this work, the best patch formulation has been identified.