title: Rapid-Onset Sildenafil Sublingual Drug Delivery Systems: In Vitro Evaluation and In Vivo Pharmacokinetic Studies in Rabbits.
abstract: The aim of the present study was to prepare sublingual delivery systems for sildenafil and evaluate its relative bioavailability after sublingual administration in rabbits to attain a rapid onset of action with good efficacy at lower doses. For sublingual application, sildenafil and its citrate were formulated in 2 different dosage forms: the first was a sublingual spray consisting of sildenafil in 2 microemulsion systems, oleic acid or propylene glycol (PG), and the second was sublingual tablets prepared with various granulated sublingual sprays adsorbed onto a silicate adsorbant (Florite(®) R), binders (Cyclocel(®) or EMDEX(®)), and disintegrants (Ac-Di-Sol(®) or Kollidon(®) CL). Results showed that sublingual absorption of sildenafil spray prepared with PG was fairly rapid. At a 0.5-mg dose, the mean onset of action was 1.3 ± 0.6 min and lasted for about 1.5 h according to the pharmacokinetic studies. In vivo studies also showed that for sublingual tablets formulated with sildenafil in PG adsorbed onto Florite(®) R at a 1:1 weight ratio then mixed with Cycloel(®) and Ac-Di-Sol(®), the onset action was fast at 1.9 ± 0.4 min and lasted for about 1 h at 0.5 mg. These findings suggest the potential for the sublingual delivery of sildenafil instead of the conventional oral administration.
authors.affiliation: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan, ROC.
authors.forename: Ming-Thau
authors.initials: MT
authors.lastname: Sheu
authors.affiliation: Department of Cosmetic Science, Providence University, Taichung City, Taiwan, ROC.
authors.forename: Chien-Ming
authors.initials: CM
authors.lastname: Hsieh
authors.affiliation: Department of Cosmetic Science and Management, Mackay Medicine, Nursing and Management College, Taipei, Taiwan, ROC.
authors.forename: Ray-Neng
authors.initials: RN
authors.lastname: Chen
authors.affiliation: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan, ROC.
authors.forename: Po-Yu
authors.initials: PY
authors.lastname: Chou
authors.affiliation: School of Pharmacy, College of Pharmacy, Taipei Medical University, Taipei 110, Taiwan, ROC. Electronic address: hsiuoho@tmu.edu.tw.
authors.forename: Hsiu-O
authors.initials: HO
authors.lastname: Ho
mesh_terms: D000286:Administration, Sublingual; D000818:Animals; D001682:Biological Availability; D004339:Drug Compounding; D016503:Drug Delivery Systems; D005079:Excipients; D006244:Hardness; D008297:Male; D019301:Oleic Acid; D014677:Pharmaceutical Vehicles; D019946:Propylene Glycol; D011817:Rabbits; D000068677:Sildenafil Citrate / Q000008:administration & dosage* / Q000493:pharmacokinetics; D012995:Solubility; D013607:Tablets; D014665:Vasodilator Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics
chemical_list: D005079:Excipients; D014677:Pharmaceutical Vehicles; D013607:Tablets; D014665:Vasodilator Agents; D019301:Oleic Acid; D019946:Propylene Glycol; D000068677:Sildenafil Citrate
keywords: bioavailability; erectile dysfunction; sildenafil; sublingual spray; sublingual tablets