impotention

sorry my pc is not whriting hebrew here i use now medicine "tesopalmed"1 for about 3 weeks its not helps at all i want to know how much time i have to take this medicine till i will know surely if it help and to keep take it or it doesnt help and to stop take it about viagra i am afraid to take it because i have problems blood presure pvc apc extrasystole thanks in advance zion