Formulating, Optimizing and Evaluation of Dutasteride Loaded Insitu-Emulgel for Androgenetic Alopecia
Authors: P. Radhakrishnan P. Radhakrishnan , G. Mariyappan G. Mariyappan , J. Karthi J. Karthi , K. Jaisumi K. Jaisumi 
Published: December 2024

delivery system, Dutasteride loaded Insitu-emulgel,
that enhances the drug's skin penetration and
reduces the dosage required to provide the targeted
effect. Additionally, it decreases adverse effects
and improves patient compliance. Dutasteride is
BCS class-II drug with high permeability and lower
solubility. Dutasteride is an antiandrogen
medication, that reduces the action of androgens on
the follicle. These androgens are responsible for
androgenic alopecia, i.e. it inhibits the enzyme 5α
reductase which is responsible for transforming
testosterone into dihydroxy testosterone and
markedly suppresses serum DHT levels. Due to the
antiandrogenic effects, it is used to treat a variety of
dermatological conditions in which androgens,
such as testosterone and dihydrotestosterone
(DHT), play a role. So, dutasteride used in
treatment of alopecia. Insitu-emulgel is more
effective than any other topical preparation. The
Insitu-emulgel also have the better loading capacity
as compared to those of the niosomes and
liposomes. Insitu-emulgel is easily removable from
skin. Insitu-emulgel give controlled release of
hydrophobic drug through skin. For the preparation
of dutasteride Insitu-emulgel – Liquid paraffin used
as a vehicle, span 20, tween 80 as emulsifier,
Propylene glycol used as a penetration enhancer,
triethanolamine as a neutralizer and ethanol used as
a solvent. Then the emulsion was incorporated into
gel base in 1:1 ratio to prepare Insitu-emulgel.
Standard graph was drawn for Dutasteride and it
was found that the solution shows linearity
(R2=0.9987 in Phosphate buffer pH 6.8) and obey
Beer‟s - Lambert‟s law with in the range of
concentration used (5 μg/ml – 25 μg/ml). The
Chemical compatibility study of Dutasteride with
excipients was carried out using IR and FTIR
Spectrometer. It revealed that there is no interaction
between the drug and excipients. Central composite
design (Design Expert, version 13, Stat Ease, Inc.)
was used to build the formulation research design,
and the formulation design was predicted and
statistically assessed. The formulation variables of
dutasteride loaded Insitu-emulgel containing 2
factors and evaluated at 2 levels. Amount of Liquid
paraffin (A, 1 ml2 ml), amount of carbopol 940 (B,
150 mg-250 mg) as independent variables and drug
release (R1), viscosity (R2) and drug content(R3)
were selected as dependent responses. A total of 13
formulations were designed by the software with 2
centre points. The selected 13 formulations were
evaluated for drug release, viscosity and drug
content. The drug release was found to be in the
range of 49.63% to70.61 %, viscosity was found to
bein the range of from 4428 to 4803 cps and drug
content was found to be in the range of 97.69% to
99.01%. By setting the criteria in the central
composite design, it suggested the Optimized
formulations. The design predicted the values of
optimized Dutasteride loaded Insitu-emulgel
formulation which was then formulated and
evaluated and the predicted value was compared
with actual value. The optimized Dutasteride
loaded Insitu-emulgel formulations was white in
colour, free from presence of particles, and showed
good homogeneity and consistency with no phase
separation. The pH of the optimized Insitu-emulgel
was found to be 6.5±0.05 pH, which lies in the
normal pH range of the skin (5.5-6.5). Thus,
indicating the skin compatibility. The Viscosity and
spreadability of Optimized dutasteride Insituemulgel formulation were found to be 4561±3.50
cps and 5.45±0.04 cm respectively, which indicates
that the formulation is neither too runny nor too
sticky and spread easily over the surface. Drug
content in the optimized Insitu-emulgel formulation
was determined by UV spectrophotometric method.
The drug content was found to be 99.01±0.08%. In
vitro Release profile of optimized formulation
showed 59.02±0.002% release upto 6 hrs. This
confirms that the drug released form the optimized
Insitu-emulgel in a controlled manner. Based on the
findings, it was determined that the Zero order
release kinetics model had the highest correlation coefficient, R
2
(0.9986),and was therefore the model
that best fit the optimized dutaste ride loaded
Insitu-emulgel. The fact that the value of "n" was
calculated to be 0.1658 (0.45 < n < 0.89), suggests
that the drug release from the polymeric matrix
follows non-Fickian or anomalous transport. A
dutasteride loaded Insitu-emulgel was developed
for topical use. When compared to other traditional
methods of administering topical medications,
Insitu-emulgel seems to be a more sophisticated
and efficient drug delivery technology. A large
number of the formulations' components are
extremely safe and stable for topical use. In order
to treat androgenetic alopecia, the present study has
succeeded in creating a topical Insitu-emulgel that
is safe, economical, and efficient. To increase the
effectiveness of treatment and patient compliance,
more clinical research is being conducted in this
area.