Design and optimization of transdermal niosomal gel loaded with paroxetine for general anxiety and panic disorders

Paroxetine is an effective serotonin reuptake inhibitor, but its bioavailability is challenged by the to hepatic first pass effect, resulting in blood level fluctuations that negatively affect its therapeutic effects. Transdermal drug delivery could be used as a solution to this issue, and noisome are suggested as a solution to penetration enhancement of drugs at this point in administration.

In the current study, paroxetine-loaded niosomes were optimized for pharmaceutical characteristics Design Expert Software (ver.7) regarding the pharmaceutical characteristics. Then, the dispersion in HPMC hydrogel medium was dispersed, and the in vivo efficacy of this drug delivery system was investigated in animal models using elevated plus maze and elevated t-maze methods.

The optimum formulation had a particle size of 417.40±28.05 nm, the particle size distribution of 0.31±, zeta potential of 12.8±0.42 mV, entrance efficiency of 72.85±0.47%, and release efficiency of 71.94±0.55%. Treatment of Bulb/c mice with this formulation via transdermal route of administration resulted in higher efficacy (p<0.05) compared with the positive and negative control groups.

The proposed formulation showed rather acceptable in vitro and in vivo efficacy, paving the ground for further investigation to choose drug products to substitute currently marketed ones.