Sloka for preventing bad dreams during sleep

Rama Skanda hanumantam vaikadeyam vrukodaram
Sayane sa smaren nityam dus-swapnam tasya nashyati

(or)

Achyutham kaes(h)avam vishNum harim somam janaardhanam
Hamsam naaraayaNam krishNam japaeth duhsvapna s(h)anthayae