I've got a bottle of phenergan, which somebody has suggested to me with a view to getting DS2 (2y 4m) to sleep through the night. He currently goes to bed sometime between 7 and 8, and sleeps until about 4/5am, often with 1 or 2 night wakings. He will still have a lunchtime nap occasionally. Later bedtimes / dropping the nap don't result in him waking up later / sleeping better. I'm on my last legs as DH has been away for over 10 weeks, and isn't due back for another 3 (so please don't judge me harshly for this).
However, I'm not sure if it will delay his wake up time - surely the effects will have worn off then?
I'm also loathe to give it as Medised / Calpol night send him loopy and stop him sleeping at all!