title: Evaluation of acyclovir cream and gel formulations for transdermal iontophoretic delivery.
abstract: BACKGROUND
  Efficient iontophoretic transdermal delivery of hydrophilic drug molecules requires selection of appropriate aqueous formulation. In this study, oil/water cream and gel formulations were investigated for iontophoretic transdermal delivery of acyclovir (ACV), a model hydrophilic small-drug molecule, across hairless rat skin on Franz diffusion cells.
  
  
  RESULTS
  Iontophoresis (0.2 mA/cm2) enhanced ACV delivery from both 5% cream (pH 6.8) and 4% gel (pH II) formulations. However, sixfold higher drug levels were delivered across the skin using gel formulation (12.25 +/- 4.04 microg/cm2) as compared with cream formulation (2.03 +/- 0.05 microg/cm2). Significantly higher drug levels were delivered when iontophoresis was performed at higher current density (0.32 mA/cm2; p < 0.05). Influence of formulation co-solvents (glycerin and propylene glycol) on drug delivery was also investigated in vitro using Franz cells and in vivo in hairless rats using microdialysis.
  
  
  CONCLUSIONS
  Iontophoretic transdermal delivery of ACV was feasible and dependent on the selection of formulation components and delivery parameters.
authors: Department of Pharmaceutical Sciences, Mercer University. 3001 Mercer University Drive, Atlanta, GA 30341, USA.
authors: Srujana
authors: S
authors: Siddoju
authors: Vishal
authors: V
authors: Sachdeva
authors: Phillip M
authors: PM
authors: Friden
authors: Ajay K
authors: AK
authors: Banga
mesh_terms: D000212:Acyclovir / Q000008:administration & dosage*; D000279:Administration, Cutaneous; D000818:Animals; D000998:Antiviral Agents / Q000008:administration & dosage*; D002626:Chemistry, Pharmaceutical; D016503:Drug Delivery Systems; D005782:Gels; D007478:Iontophoresis; D008297:Male; D009824:Ointments; D051381:Rats
chemical_list: D000998:Antiviral Agents; D005782:Gels; D009824:Ointments; D000212:Acyclovir