u take Cialis B4 30 hrs u fly ? I have never tried any sexual activity pill beforel. i plan to take half pill of Cialis prior to my 30 hours i fly. i wanna give a good performance to my girlfriend B4 we are apart for a month. ( i won't tell her that i take Cialis-- i wanna surprise her ). Will it affect my 16 hrs fly to China? Thank you so much 4 yours advices.