Zofran & Constipation

My dr gave me Rx Zofran but a side effect is constipation.  I did not have this issue prior to taking the Rx so I know that's what's causing it.  I need some relief, I'm freakin miserable.  My dr said I could take the following: colace, surfak, Metamucil, miralax and laxatives glycerin or dulcolax.  
Have any of these worked for any of you? If so which ones?
I've also tried magnesium, peppermint tea, digestive enzymes which which help just a little bit but not like I need. I'm scared to take smooth move tea... Does anyone know if it's safe during pregnancy??