Byline: K.T. Mahmood and B. Khan ABSTRACT: Sildenafil citrate is a first oral medicine approved by Food and Drug Administration (FDA), USA for treating erectile dysfunction in male. It is not registered but available in Pakistan through unlawful import. Furthermore, it is added in male sexual-enhancement products being sold fraudulently under the cover of alternate system without any medical supervision. The Drugs courts in Pakistan have acquitted such accused on the ground that no approved and validated method was available in Pakistan. The present HPLC method for the of measurement sildenafil citrate in different formulations was developed in this background. The solution at concentration of 10 ug.mL-1 was prepared with external standard Sildenafil citrate. The injection volume was 10 uL. The chromatographic separation was achieved by using a reversed phase C18 column (Phenomenex, particle size 5 mm; 4.6 mm x 150 mm).