Is It Safe To Switch From Tri-cyclin Lo To Primolut N To Stop Bleeding?

hi..i want to know if I can switch from tri-cyclin lo to Primolut N after already taking tri cyclin-lo for 24 days. I want to change my pills as i m experincing light vaginal bleeding for the past 12 to 13 days. Is it safe to switch from tri-cyclin lo to Primolut N to stop the bleeding?...please let me know as it is really urgent!